Add punctuation to alt text.

Author: LJSpiller

articles/azure-functions/start-stop-vms/pre-actions.md

@@ -38,7 +38,7 @@ The steps in this section require the `ststv2_vms_Scheduled_start` logic app tha
 
  1. In the Logic Apps Designer page, select **Function-Try** and then select **Add an action**.
 
-    :::image type="content" source="./media/pre-actions/add-action-button.png" alt-text="Screenshot of the Logic Apps designer showing Add an Action button location":::
+    :::image type="content" source="./media/pre-actions/add-action-button.png" alt-text="Screenshot of the Logic Apps designer showing Add an Action button location.":::
 
  5. Choose **HTTP**, select the HTTP **Method**, and add the **URL**. This HTTP request will be the pre-action for the scheduled start action, after you change the action order in **Function-Try**. You can also configure the HTTP action at a later time.