Resolve #3421335 "Only require gtag.ajax if other ajax libs are added."

Closes #3421335

Here is my .lando.yml file for easy review and development.

name: google_tag
recipe: drupal10
config:
  php: '8.2'
  via: apache:2.4
  webroot: web
  database: mariadb:10.4
  xdebug: false
services:
  database:
    type: compose
    services:
      image: mariadb:10.4
      command: docker-entrypoint.sh mariadbd
      restart: always
      ports:
        - '3306'
      environment:
        MARIADB_ALLOW_EMPTY_ROOT_PASSWORD: 'true'
        MARIADB_DATABASE: drupal10
        MYSQL_DATABASE: drupal10
        MARIADB_USER: drupal10
        MARIADB_PASSWORD: drupal10
  appserver:
    overrides:
      environment:
        SIMPLETEST_DB: 'mysql://drupal10:drupal10@database/drupal10'
        SIMPLETEST_BASE_URL: 'http://appserver'
      volumes:
        # Don't share our host working directory as /app. We want /app empty for composer.
        - /app
        # Instead share our host working directory as a standalone package.
        - .:/usr/local/google_tag
    build:
      # Create a new Drupal project and use the module as a non-packagist repository.
      - composer create-project --dev drupal/recommended-project:10.2.x /app
      - composer config extra.enable-patching true
      - composer config extra.composer-exit-on-patch-failure true
      - composer config allow-plugins.cweagans/composer-patches true
      - composer require cweagans/composer-patches
      - composer config minimum-stability dev
      - composer config allow-plugins.phpstan/extension-installer true
      - composer require --dev drupal/core-dev:^10.2 drush/drush phpspec/prophecy-phpunit:* phpstan/extension-installer mglaman/phpstan-drupal phpstan/phpstan-deprecation-rules drupal/config_inspector
      - composer config repositories.localdev path /usr/local/google_tag && composer require drupal/google_tag:\*@dev
tooling:
  # Provide a command to install Drupal.
  install:
    service: appserver
    cmd:
      - /app/vendor/bin/drush --root=/app/web site:install --account-mail=noreply@example.com --account-name=admin --account-pass=admin --db-url=mysql://drupal10:drupal10@database:3306/drupal10 -y --verbose
      - /app/vendor/bin/drush en -y google_tag
  # Provide Drush tooling to automatically know the Drupal root.
  drush:
    service: appserver
    cmd: /app/vendor/bin/drush --root=/app/web
  phpcs:
    service: appserver
    cmd: /app/vendor/bin/phpcs -s --colors --standard=Drupal,DrupalPractice --extensions=php,module,inc,install,test,profile,theme,css,info,txt,md,yml web/modules/contrib/google_tag
  # Provide PHPCBF tooling to fix coding standards.
  phpcbf:
    service: appserver
    cmd: /app/vendor/bin/phpcbf -s --colors --standard=Drupal,DrupalPractice --extensions=php,module,inc,install,test,profile,theme,css,info,txt,md,yml web/modules/contrib/google_tag
  # Provide phpstan tooling to check for code quality and deprecated code.
  phpstan:
    service: appserver
    cmd: /app/vendor/bin/phpstan analyse --configuration web/modules/contrib/google_tag/phpstan.neon web/modules/contrib/google_tag
  # Provide phpunit tooling to run unit tests.
  phpunit:
    service: appserver
    cmd: /app/vendor/bin/phpunit --configuration /app/web/core/phpunit.xml.dist --bootstrap /app/web/core/tests/bootstrap.php /app/web/modules/contrib/google_tag

If I print the $attachments var in the event subscriber on a views page with ajax enabled, here is what I see.

array:6 [▼
  "html_head" => array:6 [▼
    0 => array:2 [▼
      0 => array:3 [▼
        "#tag" => "meta"
        "#noscript" => true
        "#attributes" => array:2 [▶]
      ]
      1 => "big_pipe_detect_nojs"
    ]
    1 => array:2 [▼
      0 => array:3 [▼
        "#tag" => "meta"
        "#attributes" => array:1 [▶]
        "#weight" => -1000
      ]
      1 => "system_meta_content_type"
    ]
    2 => array:2 [▼
      0 => array:3 [▼
        "#type" => "html_tag"
        "#tag" => "meta"
        "#attributes" => array:2 [▶]
      ]
      1 => "system_meta_generator"
    ]
    3 => array:2 [▼
      0 => array:2 [▼
        "#tag" => "meta"
        "#attributes" => array:2 [▶]
      ]
      1 => "MobileOptimized"
    ]
    4 => array:2 [▼
      0 => array:2 [▼
        "#tag" => "meta"
        "#attributes" => array:2 [▶]
      ]
      1 => "HandheldFriendly"
    ]
    5 => array:2 [▼
      0 => array:2 [▼
        "#tag" => "meta"
        "#attributes" => array:2 [▼
          "name" => "viewport"
          "content" => "width=device-width, initial-scale=1.0"
        ]
      ]
      1 => "viewport"
    ]
  ]
  "library" => array:22 [▼
    0 => "contextual/drupal.contextual-links"
    1 => "system/base"
    2 => "olivero/global-styling"
    3 => "core/drupal.active-link"
    4 => "google_tag/gtm"
    5 => "google_tag/gtag"
    6 => "olivero/powered-by-block"
    7 => "olivero/feed"
    8 => "views/views.module"
    9 => "views/views.ajax"
    10 => "views/views.module"
    11 => "views/views.ajax"
    12 => "olivero/navigation-secondary"
    13 => "olivero/search-wide"
    14 => "olivero/navigation-primary"
    15 => "olivero/search-narrow"
    16 => "toolbar/toolbar"
    17 => "devel/devel-toolbar"
    18 => "user/drupal.user.icons"
    19 => "contextual/drupal.contextual-toolbar"
    20 => "shortcut/drupal.shortcut"
    21 => "toolbar/toolbar.escapeAdmin"
  ]
  "html_head_link" => array:3 [▼
    0 => array:1 [▼
      0 => array:3 [▼
        "rel" => "icon"
        "href" => "/core/themes/olivero/favicon.ico"
        "type" => "image/vnd.microsoft.icon"
      ]
    ]
    1 => array:1 [▼
      0 => array:4 [▼
        "rel" => "alternate"
        "type" => "application/rss+xml"
        "title" => ""
        "href" => "https://googletag.lndo.site/rss.xml"
      ]
    ]
    2 => array:1 [▼
      0 => array:4 [▼
        "rel" => "alternate"
        "type" => "application/rss+xml"
        "title" => ""
        "href" => "https://googletag.lndo.site/rss.xml"
      ]
    ]
  ]
  "html_response_attachment_placeholders" => array:4 [▼
    "styles" => "<css-placeholder token="KTHomi4oxQStb6_W1b9JhpxkZk7mzIV48BS08OSfmDca340JVON7GayNFnEVz3PkCQ_d49zfsA">"
    "scripts" => "<js-placeholder token="KTHomi4oxQStb6_W1b9JhpxkZk7mzIV48BS08OSfmDca340JVON7GayNFnEVz3PkCQ_d49zfsA">"
    "scripts_bottom" => "<js-bottom-placeholder token="KTHomi4oxQStb6_W1b9JhpxkZk7mzIV48BS08OSfmDca340JVON7GayNFnEVz3PkCQ_d49zfsA">"
    "head" => "<head-placeholder token="KTHomi4oxQStb6_W1b9JhpxkZk7mzIV48BS08OSfmDca340JVON7GayNFnEVz3PkCQ_d49zfsA">"
  ]
  "drupalSettings" => array:5 [▼
    "gtm" => array:2 [▼
      "tagIds" => array:1 [▶]
      "settings" => array:7 [▼
        "data_layer" => "dataLayer"
        "include_classes" => false
        "allowlist_classes" => ""
        "blocklist_classes" => ""
        "include_environment" => false
        "environment_id" => ""
        "environment_token" => ""
      ]
    ]
    "gtag" => array:5 [▼
      "tagId" => ""
      "otherIds" => []
      "consentMode" => false
      "events" => []
      "additionalConfigInfo" => []
    ]
    "views" => array:2 [▼
      "ajax_path" => "/views/ajax"
      "ajaxViews" => array:1 [▶]
    ]
    "ajaxTrustedUrl" => array:1 [▼
      "/search/node" => true
    ]
    "toolbar" => array:2 [▼
      "breakpoints" => array:3 [▶]
      "subtreesHash" => "g0npP83EmiVh3S33o-B8LQZZ626GNz6wn7pWNrFjXD0"
    ]
  ]
  "placeholders" => array:6 [▼
    "<drupal-render-placeholder callback="Drupal\Core\Render\Element\StatusMessages::renderMessages" arguments="0" token="_HAdUpwWmet0TOTe2PSiJuMntExoshbm1kh2wQzzzAA"></drupal-render-placeholder>" => array:1 [▶]
    "<drupal-render-placeholder callback="announcements_feed.lazy_builders:renderAnnouncements" token="m--BNYDqgTao0j2QoLFf1TwfQN-Bm9xPlckw9QAC1h4"></drupal-render-placeholder>" => array:2 [▶]
    "<drupal-render-placeholder callback="devel.lazy_builders:renderMenu" token="3SaamyNrJZMMYe_kyv4Lc7-K5z3OkYidDaYEaMx_yVs"></drupal-render-placeholder>" => array:1 [▶]
    "<drupal-render-placeholder callback="user.toolbar_link_builder:renderToolbarLinks" token="QPmvukHqpEJJ4rYEzUUFx0ERxrtfmQ9TMOp_hvyLHEk"></drupal-render-placeholder>" => array:2 [▶]
    "<drupal-render-placeholder callback="user.toolbar_link_builder:renderDisplayName" token="XGROnxBLjNjdNZJ_VcOhVZtenx2tDkIKPfojS_uZFXA"></drupal-render-placeholder>" => array:2 [▶]
    "<drupal-render-placeholder callback="shortcut.lazy_builders:lazyLinks" token="5-XBI-QHgyU_l7Bu0FizHR7YBqK2bTVTBFF8Z0DVTis"></drupal-render-placeholder>" => array:3 [▶]
  ]
]