Using workflow concurrency

Author: gastaldi

.github/workflows/build.yml

@@ -4,16 +4,15 @@ on:
   pull_request:
     types: [opened, synchronize]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-        with:
-          ref: refs/pull/${{ github.event.pull_request.number }}/merge
-      - uses: n1hility/cancel-previous-runs@v2
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Set up ruby
         uses: ruby/setup-ruby@v1