Issue #3517495 by dydave: Broadened Tests coverage on Gitlab CI and required jobs to pass.

https://www.drupal.org/project/structure_sync/issues/3517495

Gitlab CI: Broadened Tests coverage and required jobs to pass: CSPELL, ESLINT, PHPCS, PHPSTAN.

.gitlab-ci.yml

@@ -27,8 +27,69 @@ include:
 #   SKIP_ESLINT: '1'
 #   OPT_IN_TEST_NEXT_MAJOR: '1'
 #   _CURL_TEMPLATES_REF: 'main'
+
+################
+# Structure Sync: Pipeline configuration variables and custom jobs, mostly:
+#  - Broaden test coverage to all supported core versions and max PHP.
+#  - Require all jobs to pass: CSpell, ESLint, PHPCS and PHPSTAN.
+################
+
 variables:
-  OPT_IN_TEST_PREVIOUS_MAJOR: '1'
-  OPT_IN_TEST_CURRENT: '1'
-  OPT_IN_TEST_NEXT_MAJOR: '0'
-  RUN_JOB_UPGRADE_STATUS: '0'
+  ################
+  # Opt in variables: Broaden test coverage.
+  ################
+  OPT_IN_TEST_CURRENT: 1
+  OPT_IN_TEST_PREVIOUS_MAJOR: 1
+  OPT_IN_TEST_PREVIOUS_MINOR: 1
+  OPT_IN_TEST_NEXT_MINOR: 1
+  OPT_IN_TEST_NEXT_MAJOR: 1
+  OPT_IN_TEST_MAX_PHP: 1
+  # Speed up the execution of the Tests.
+  _PHPUNIT_CONCURRENT: 1
+  # # Convenient for debugging: Enable in issue forks for testing.
+  # _SHOW_ENVIRONMENT_VARIABLES: 1
+
+  # Strict PHPSTAN validation: Enforce the *maximum* rule level: 9.
+  # _PHPSTAN_LEVEL: 9
+
+#
+# CSPELL overrides and configuration.
+#
+cspell:
+  # Require spellcheck to pass.
+  allow_failure: false
+
+#
+# ESLINT overrides and configuration.
+#
+eslint:
+  # Require eslint to pass.
+  allow_failure: false
+
+#
+# PHPCS overrides and configuration.
+#
+phpcs:
+  # Require phpcs to pass.
+  allow_failure: false
+
+#
+# PHPSTAN overrides and configuration.
+#
+phpstan:
+  # Require phpstan to pass.
+  allow_failure: false
+
+# #
+# # PHPUNIT overrides and configuration.
+# #
+# phpunit:
+#   # Require phpunit to pass.
+#   allow_failure: false
+
+# #
+# # STYLELINT overrides and configuration.
+# #
+# stylelint:
+#   # Require stylelint to pass.
+#   allow_failure: false