Enable merge queues

Signed-off-by: Stephen Finucane <stephen@that.guru>

Author: stephenfin

.github/workflows/ci.yaml

@@ -1,11 +1,12 @@
 ---
 name: CI
 on:
+  merge_group:
+  pull_request:
   push:
     branches:
       - main
       - stable/*
-  pull_request:
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
   cancel-in-progress: true