Fix incorrect syntax for showing a notification while executing custom queries

packages/client/src/utils/buttonActions.js

@@ -127,7 +127,7 @@ const queryExecutionHandler = async action => {
     // Trigger a notification and invalidate the datasource as long as this
     // was not a readable query
     if (!query.readable) {
-      API.notifications.error.success("Query executed successfully")
+      notificationStore.actions.success("Query executed successfully")
       await dataSourceStore.actions.invalidateDataSource(query.datasourceId)
     }