Update alert with acknowledge example (#16646)

Co-authored-by: Franck Nijhof <frenck@frenck.nl>

source/_integrations/alert.markdown

@@ -252,7 +252,9 @@ Some notifiers support more parameters (e.g., to set text color or action
 # Example configuration.yaml entry
 alert:
   garage_door:
-    name: Garage is open
+    name: "Garage is open"
+    message: "The garage door is still open"
+    done_message: "The garage door is closed"
     entity_id: input_boolean.garage_door
     state: "on"   # Optional, 'on' is the default value
     repeat:
@@ -270,4 +272,20 @@ alert:
 This particular example relies on the `inline_keyboard` functionality of
 Telegram, where the user is presented with buttons to execute certain actions.
 
+Based on the example above you can make an automation to stop further messages,
+but you will still receive the done message.
+
+```yaml
+- alias: "Telegram callback to stop alerts for garage door"
+  trigger:
+    - platform: event
+      event_type: telegram_callback
+      event_data:
+        data: "/garage_acknowledge"
+  action:
+    - service: alert.turn_off
+      target:
+        entity_id: alert.garage_door
+```
+
 [template]: /docs/configuration/templating/