Bring back required instance ci template setting in database

.rubocop_todo/rspec/named_subject.yml

app/controllers/admin/application_settings_controller.rb

app/views/admin/application_settings/ci_cd.html.haml

config/feature_flags/beta/required_pipelines.yml

...lication_settings_required_instance_ci_template_column.rb

db/schema_migrations/20240904220102

db/structure.sql

doc/administration/settings/continuous_integration.md

doc/ci/yaml/index.md

...admin/application_settings/ci_cd/ci_template_dropdown.vue

...scripts/pages/admin/application_settings/ci_cd/helpers.js

...vascripts/pages/admin/application_settings/ci_cd/index.js

...p/controllers/ee/admin/application_settings_controller.rb

ee/app/models/ee/application_setting.rb

...lication_settings/_required_instance_ci_setting.html.haml

ee/lib/ee/gitlab/ci/config_ee.rb

ee/lib/gitlab/ci/config/required/processor.rb

...controllers/admin/application_settings_controller_spec.rb

...n/application_settings/ci_cd/ci_template_dropdown_spec.js

...nd/pages/admin/application_settings/ci_cd/helpers_spec.js