Update groups services to handle web_based_commit_signing_enabled

• Groups::UpdateService should handle web_based_commit_signing_enabled.
  • When it is enabled lock_web_based_commit_signing_enabled should also be true
  • When it is changes from enabled to disabled lock_web_based_commit_signing_enabled should also be changed to false
  • This setting is only for top-level groups. It should not be set on subgroups.