Cancel in-progress workflow runs on new commits

Author: jeromegamez

.github/workflows/tests.yml

@@ -18,6 +18,10 @@ on:
       - "composer.json"
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   test:
     name: >