tests(action): Stop other running tests

Author: LukeSavefrogs

.github/workflows/test-action.yml

@@ -6,6 +6,10 @@ on:
   push:
   pull_request:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+    
 jobs:
   test:
     name: "Test action"