Merge branch 'group-level-integrations-feature-flag' into 'master'

Add group_level_integrations feature flag info

See merge request gitlab-org/gitlab!42454

config/feature_flags/development/group_level_integrations.yml

 ---
 name: group_level_integrations
 introduced_by_url: 
-rollout_issue_url: 
-group: 
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/238575
+group: group::ecosystem
 type: development
 default_enabled: false