Update pull_request_event_api_properties.md

Author: Mini256

data/reusables/webhooks/pull_request_event_api_properties.md

@@ -1,3 +1,3 @@
 Key | Type | Description
 ----|------|-------------
-`action`|`string` | The action that was performed. Can be one of `opened`, `closed`, `reopened`, `assigned`, `unassigned`, `review_requested`, `review_request_removed`, `labeled`, `unlabeled`, and `synchronize`.
+`action`|`string` | The action that was performed. Can be one of `opened`, `edited`, `closed`, `reopened`, `assigned`, `unassigned`, `review_requested`, `review_request_removed`, `labeled`, `unlabeled`, and `synchronize`.