Disable eager loading in Rails 7

Rails 7 eager loads classes in test environment when a CI is detected.

This behavior causes Zeitwerk issues when trying to eager load
Active Admin files placed under `test_apps/rails_70/app/admin/`, because
they are not excluded by `remove_active_admin_load_paths_from_rails_autoload_and_eager_load`

This commit ensures that eager loading is disabled in test app's test
environment

spec/support/rails_template.rb

@@ -50,6 +50,11 @@
 
 copy_file File.expand_path("templates/models/tagging.rb", __dir__), "app/models/tagging.rb"
 
+# Rails 7: do not eager load classes to prevent Zeitwerk errors in test_app
+gsub_file "config/environments/test.rb", /  config.eager_load = ENV\["CI"\].present\?/, <<-RUBY
+  config.eager_load = false
+RUBY
+
 gsub_file "config/environments/test.rb", /  config.cache_classes = true/, <<-RUBY
 
   config.cache_classes = !ENV['CLASS_RELOADING']