CI concurrency for lint

Author: tupui

.github/workflows/lint.yml

@@ -5,6 +5,10 @@ on:
   push:
     branches: [main]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   linter:
     runs-on: ubuntu-latest