Move `Gitlab/DocUrl` to `Gitlab/DocumentationLinks/HardcodedUrl`

.rubocop.yml

.rubocop_todo/gitlab/documentation_links/hardcoded_url.yml

...todo/layout/line_end_string_concatenation_indentation.yml

app/views/layouts/header/_openssl_callout.html.haml

app/views/shared/_visibility_radios.html.haml

config/initializers/safe_session_store_patch.rb

ee/app/helpers/admin/application_settings_helper.rb

...orkers/vulnerabilities/mark_dropped_as_resolved_worker.rb

ee/lib/gitlab/duo/developments/setup.rb

ee/lib/gitlab/product_analytics/developments/setup.rb

gems/config/rubocop.yml

keeps/delete_obsolete_advanced_search_migrations.rb

keeps/delete_old_feature_flags.rb

keeps/mark_old_advanced_search_migrations_as_obsolete.rb

keeps/overdue_finalize_background_migration.rb

lib/generators/gitlab/usage_metric_definition_generator.rb

lib/gitlab/database/dictionary.rb

lib/gitlab/database/gitlab_schema.rb

rubocop/cop/gitlab/doc_url.rb

rubocop/cop/gitlab/documentation_links/hardcoded_url.rb