add oxford comma

Author: Jak-MS

articles/data-factory/monitor-visually.md

@@ -111,7 +111,7 @@ You can rerun activities inside a pipeline. Select **View activity runs**, and t
 
 ### Rerun from failed activity
 
-If an activity fails, times out or is cancelled, you can rerun the pipeline from that failed activity by selecting **Rerun from failed activity**.
+If an activity fails, times out, or is cancelled, you can rerun the pipeline from that failed activity by selecting **Rerun from failed activity**.
 
 ![Rerun failed activity](media/monitor-visually/rerun-failed-activity.png)