Fix persistent volume app scale down warning

App ids tend to be rather log, as they include the full group path. Thus
they should not be used in dialog titles and any other place that has
limited space. Adjust the persistent volume app scale down warning as
the dialog title should not include the app id, for the given reason.

src/js/mixins/AppActionsHandlerMixin.jsx

@@ -217,7 +217,7 @@ var AppActionsHandlerMixin = {
       actionButtonLabel: "Continue Scaling",
       message: (
         <div>
-          <div>Scaling down will cause any existing local volumes to
+          <div>Scaling down ${appId} will cause any existing local volumes to
             be detached from destroyed instances. <a href="about:blank"
                 target="_blank"
                 className="modal-body-link">
@@ -230,7 +230,7 @@ var AppActionsHandlerMixin = {
         </div>
       ),
       severity: DialogSeverity.WARNING,
-      title: `Caution: ${appId} is a stateful application`
+      title: "Scale Stateful Application"
     });
 
     DialogStore.handleUserResponse(dialogId, () => {