Prevent concurrent runs

.github/workflows/i18n-automerge.yml

@@ -11,6 +11,9 @@ jobs:
       github.event.pull_request.base.ref == 'main' &&
       github.event.pull_request.head.ref == 'l10n_main'
     runs-on: ubuntu-latest
+    concurrency:
+      group: ${{ github.workflow }}-${{ github.ref }}
+      cancel-in-progress: true
 
     steps:
       - name: Checkout code