Make register rule independent of admin rule

app/policies/group_policy.rb

@@ -163,6 +163,7 @@ class GroupPolicy < Namespaces::GroupProjectNamespaceSharedPolicy
     enable :create_projects
     enable :admin_pipeline
     enable :admin_group_runners
+    enable :register_group_runners
     enable :admin_build
     enable :read_cluster
     enable :add_cluster
@@ -207,10 +208,6 @@ class GroupPolicy < Namespaces::GroupProjectNamespaceSharedPolicy
     enable :read_nested_project_resources
   end
 
-  rule { can?(:admin_group_runners) }.policy do
-    enable :register_group_runners
-  end
-
   rule { owner }.enable :create_subgroup
   rule { maintainer & maintainer_can_create_group }.enable :create_subgroup