Enable GraphQL Runner API

This change enables the GraphQL API for administration of runners. It
enables several GraphQL queries and mutations that enable
administrators to manage their runner fleet programmatically.

The new APIs are made available by setting the feature flag
"runner_graphql_query" to enabled by default.

Changelog: added

config/feature_flags/development/runner_graphql_query.yml

@@ -4,5 +4,5 @@ introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/59763
 rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/328700
 type: development
 group: group::runner
-default_enabled: false
+default_enabled: true
 milestone: '13.12'