ci: preserve membrowse push-to-master runs from cancellation

Use unique concurrency group per commit for push events so that
sequential merges to master don't cancel each other's queued runs.
This ensures every master commit gets analyzed for memory tracking.

Author: michael-membrowse

.github/workflows/membrowse-report.yml

@@ -7,7 +7,7 @@ on:
       - master
 
 concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
+  group: ${{ github.workflow }}-${{ github.event_name == 'push' && github.sha || github.ref }}
   cancel-in-progress: ${{ github.event_name == 'pull_request' }}
 
 jobs: