chore: Update the documentation for configuring webhooks in the account (#4703)

swagger/parameters/index.yml

@@ -25,6 +25,9 @@ conversation_id:
 custom_filter_id:
   $ref: ./custom_filter_id.yml
 
+webhook_id:
+  $ref: ./webhook_id.yml
+
 message_id:
   $ref: ./message_id.yml
 

swagger/parameters/webhook_id.yml

@@ -0,0 +1,5 @@
+in: path
+name: webhook_id
+type: integer
+required: true
+description: The numeric ID of the webhook