MTFF: Allow viewers access in cloud (#114607)

* Reapply "K8s: read resource configs from API Enablement for API Builders" (#114475)

This reverts commit 4130bd9cd3.

* revert part that broke things

* FF service changes are gonna come later

* MTFF: allow viewers access to MTFF by enforcing runtime_config for custom routes

* unused var

* removed now

* pass the test, include defaults

* revert sample.ini change

pkg/tests/apis/plugins/discovery_test.go

@@ -13,7 +13,8 @@ func TestIntegrationPluginsIntegrationDiscovery(t *testing.T) {
 
 	t.Run("discovery", func(t *testing.T) {
 		helper := setupHelper(t)
-		disco := helper.GetGroupVersionInfoJSON("plugins.grafana.app")
+		disco, err := helper.GetGroupVersionInfoJSON("plugins.grafana.app")
+		require.NoError(t, err)
 		require.JSONEq(t, `[
 			{
 				"version": "v0alpha1",