Update build_nix.yml

.github/workflows/build_nix.yml

@@ -5,18 +5,16 @@ on:
     - cron: '0 0 * * 1'
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ (github.ref == 'refs/heads/main' && github.run_number) || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
     timeout-minutes: 60
     if: ${{ github.actor != 'dependabot[bot]' }}
     steps:
-      - uses: styfle/[email protected]
-        name: Cancel Outdated Builds
-        with:
-          all_but_latest: true
-          access_token: ${{ github.token }}
-
       - name: Install Nix
         uses: cachix/install-nix-action@v25