ci: add concurrency group to release workflow

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: mridang

.github/workflows/release.yml

@@ -12,6 +12,10 @@ defaults:
   run:
     working-directory: ./
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: false
+
 jobs:
   publish-package:
     runs-on: ubuntu-latest