ci: add merge queue

Author: ctron

.github/workflows/ci.yaml

@@ -9,8 +9,9 @@ on:
   # Also on PRs, just be careful not to publish anything
   pull_request:
   # Allow to be called from other workflows (like "release")
-  workflow_call:
-  # But don't trigger on tags, as they are covered by the "release.yaml" workflow
+  merge_group:
+    types:
+      - checks_requested
 
 jobs: