Fix drush generation error: The reserved indicator @ cannot start a plain...

Fix drush generation error: The reserved indicator @ cannot start a plain scalar; you need to quote the scalar

simple_sitemap.services.yml

@@ -3,28 +3,28 @@ services:
     class: Drupal\simple_sitemap\Simplesitemap
     public: true
     arguments:
-      - @simple_sitemap.sitemap_generator
-      - @config.factory
-      - @database
-      - @entity_type.manager
-      - @path.validator
-      - @date.formatter
+      - '@simple_sitemap.sitemap_generator'
+      - '@config.factory'
+      - '@database'
+      - '@entity_type.manager'
+      - '@path.validator'
+      - '@date.formatter'
 
   simple_sitemap.sitemap_generator:
     class: Drupal\simple_sitemap\SitemapGenerator
     public: false
     arguments:
-      - @simple_sitemap.batch
-      - @database
-      - @module_handler
-      - @language_manager
+      - '@simple_sitemap.batch'
+      - '@database'
+      - '@module_handler'
+      - '@language_manager'
 
   simple_sitemap.form_helper:
     class: Drupal\simple_sitemap\Form\FormHelper
     public: true
     arguments:
-      - @simple_sitemap.generator
-      - @current_user
+      - '@simple_sitemap.generator'
+      - '@current_user'
 
   simple_sitemap.batch:
     class: Drupal\simple_sitemap\Batch\Batch
@@ -34,19 +34,19 @@ services:
     class: Drupal\simple_sitemap\Batch\BatchUrlGenerator
     public: true
     arguments:
-      - @simple_sitemap.sitemap_generator
-      - @language_manager
-      - @entity_type.manager
-      - @path.validator
-      - @entity.query
-      - @simple_sitemap.logger
+      - '@simple_sitemap.sitemap_generator'
+      - '@language_manager'
+      - '@entity_type.manager'
+      - '@path.validator'
+      - '@entity.query'
+      - '@simple_sitemap.logger'
 
   simple_sitemap.logger:
     class: Drupal\simple_sitemap\Logger
     prublic: false
     arguments:
-      - @logger.channel.simple_sitemap
-      - @current_user
+      - '@logger.channel.simple_sitemap'
+      - '@current_user'
 
   logger.channel.simple_sitemap:
     parent: logger.channel_base