Remove redundant query whitelisting

This removes a redunant query limit whitelisting rule from the Groups
API. This can be removed because another entry exists a few lines down.

lib/api/groups.rb

@@ -210,8 +210,6 @@ module API
 
       desc 'Remove a group.'
       delete ":id" do
-        Gitlab::QueryLimiting.whitelist('https://gitlab.com/gitlab-org/gitlab-ee/issues/4795')
-
         group = find_group!(params[:id])
         authorize! :admin_group, group