.github/workflows: add a dev queue for GitHub Actions hacking
diff --git a/.github/workflows/queue-main.yml b/.github/workflows/queue-main.yml
index ade8791..e66f15f 100644
--- a/.github/workflows/queue-main.yml
+++ b/.github/workflows/queue-main.yml
@@ -6,6 +6,8 @@
 # cannot be pushed cleanly because it needs to be rebased, which
 # will happen especially if another developer pushes a change at
 # roughly the same time.
+#
+# Please keep this file in sync with queue-dev.yml.
 
 name: Main Branch Commit Queue
 on: