chore: Move deployment UI and HA into experimental (#4595)

These are new, so they deserve a bit of gel-time!

enterprise/coderd/coderd.go

@@ -267,7 +267,7 @@ func (api *API) updateEntitlements(ctx context.Context) error {
 
 	if changed, enabled := featureChanged(codersdk.FeatureHighAvailability); changed {
 		coordinator := agpltailnet.NewCoordinator()
-		if enabled {
+		if api.Experimental && enabled {
 			haCoordinator, err := tailnet.NewCoordinator(api.Logger, api.Pubsub)
 			if err != nil {
 				api.Logger.Error(ctx, "unable to set up high availability coordinator", slog.Error(err))