Switch to GHMQ

Author: eldruin

.github/bors.toml

@@ -1,7 +1,9 @@
 on:
-  push:
-    branches: [ staging, trying, master ]
-  pull_request:
+  push: # Run CI for all branches except GitHub merge queue tmp branches
+    branches-ignore:
+    - "gh-readonly-queue/**"
+  pull_request: # Run CI for PRs on any branch
+  merge_group: # Run CI for the GitHub merge queue
 
 name: CI