Remove allow_members_to_see_invited_groups_in_access_dropdowns flag

This flag is fully enabled

Changelog: fixed
EE: true
Contributes to: https://gitlab.com/gitlab-org/gitlab/-/issues/438145

config/feature_flags/gitlab_com_derisk/allow_members_to_see_invited_groups_in_access_dropdowns.yml

----
-name: allow_members_to_see_invited_groups_in_access_dropdowns
-feature_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/345140
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/140927
-rollout_issue_url: https://gitlab.com/gitlab-com/gl-infra/production/-/issues/17364
-milestone: '16.8'
-group: group::source code
-type: gitlab_com_derisk
-default_enabled: false

doc/user/project/members/index.md

@@ -157,7 +157,7 @@ To add a group to a project:
 
 The invited group is displayed on the **Groups** tab.
 Private groups are masked from unauthorized users.
-With the feature flag `allow_members_to_see_invited_groups_in_access_dropdowns` enabled, private groups are displayed in project settings for protected branches, protected tags, and protected environments.
+Private groups are displayed in project settings for protected branches, protected tags, and protected environments.
 The members of the invited group are not displayed on the **Members** tab.
 The **Members** tab shows:
 

ee/app/finders/autocomplete/project_invited_groups_finder.rb

@@ -42,11 +42,6 @@ def invited_groups(project)
     def with_project_access?(project)
       return false unless params[:with_project_access].present?
 
-      return false unless Feature.enabled?(:allow_members_to_see_invited_groups_in_access_dropdowns,
-        project,
-        type: :gitlab_com_derisk
-      )
-
       project.member?(current_user, Gitlab::Access::MAINTAINER)
     end
   end