Add pull request trigger for closed trigger type (#6)

For some reason, it does not seem to trigger for `pull_request_target` right now; it might be related to merge queues only (since it seems to have closed others properly when merge queues are not involved), but it leaves exceptions requests pull requests open instead of tagging them properly and closing them.

Author: xaf

.github/workflows/artikodin.yaml

@@ -19,6 +19,13 @@ on:
     branch:
       - main
 
+  # This does not work on forks, we are duplicating
+  # the 'closed' call here because it does not seem
+  # to behave as expected for `pull_request_target`.
+  pull_request:
+    types:
+      - closed
+
   # Runs on a merge group build
   merge_group:
     types: