Update notifications.md to include from_account

This PR is dependent on another PR getting merged: mastodon/mastodon#10796 . If that PR is not accepted, this can also be closed

Author: Paul

content/en/api/rest/notifications.md

@@ -25,6 +25,7 @@ Returns array of [Notification]({{< relref "entities.md#notification" >}})
 | `min_id` | Return results immediately newer than ID | Optional ||
 | `limit` | Maximum number of results | Optional | 20 |
 | `exclude_types` | Array of types to exclude (e.g. `follow`, `favourite`, `reblog`, `mention`) | Optional ||
+| `from_account` | username@domain of user to include | Optional ||
 
 ### Pagination