Adds Xiaomi double button click example (#4468)

* added example for smart button double click

* added example for smart button double click

source/_components/xiaomi_aqara.markdown

@@ -222,6 +222,25 @@ This example plays the sound of a dog barking when the button is held down and s
       gw_mac: xxxxxxxxxxxx
 ```
 
+### {% linkable_title Double Click on Smart Button %}
+
+This example toggles the living room lamp on a double click of the button.
+
+```yaml
+- alias: Double Click to toggle living room lamp
+  trigger:
+    platform: event
+    event_type: click
+    event_data:
+      entity_id: binary_sensor.switch_158d000xxxxxc2
+      click_type: double
+  action:
+    service: light.toggle
+    data:
+      entity_id: light.living_room_lamp
+```
+
+
 ## {% linkable_title Troubleshooting %}
 
 ### {% linkable_title Initial setup problem %}