* ee/master: (25 commits)
  Introduce namespace license checks for Push Rules (EES)
  Use a named subject in `models/ee/board_spec.rb`
  Hide the milestone variable on board when the feature is disabled
  Hide the milestone in the API when the feature is not available
  Don't update milestones on boards if the feature is not available
  Hide editing/creating milestones from the board UI
  Add `issue_board_milestone` feature to license
  Split Projects:Settings::RepositoryController into CE and EE sections
  Refactor Projects::CreateService and specs to make EE-only code clearer
  Fix EE conflicts for "Allow unauthenticated access to the `/api/v4/users` API"
  Introduce namespace license checks for merge request approvers (EES)
  Remove an unnecessary "included do ... end" block in app/models/concerns/approvable.rb
  Raise an error if an unknown feature is passed to stub_licensed_features
  Don't show Issue/MR template Setting if feature not available
  Only set MR description from template when feature available
  Only set issues template from setting if feature available
  Add Issuable Default Template feature to License
  Update CHANGELOG.md for 9.3.4
  Update CHANGELOG-EE.md for 9.3.4-ee
  Hide `Focus mode` on issue boards
  ...