Cancel older builds on GH Actions (#2215)

Author: sfc-gh-jszczerbinski

.github/workflows/build_test.yml

@@ -23,6 +23,11 @@ on:
           tags:
             description: "Test scenario tags"
 
+concurrency:
+  # older builds for the same pull request numer or branch should be cancelled
+  cancel-in-progress: true
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+
 jobs:
   lint:
     name: Check linting