chore(deps): update grafana/shared-workflows digest to a4723c4

Author: renovate[bot]

.github/workflows/self-zizmor.yaml

@@ -41,7 +41,7 @@ jobs:
       - zizmor-check
     if: ${{ needs.zizmor-check.outputs.found-files == 'true' }}
 
-    uses: grafana/shared-workflows/.github/workflows/reusable-zizmor.yml@7c748d77ca1ccc01af4281ea72c7ec9d2b3d9129
+    uses: grafana/shared-workflows/.github/workflows/reusable-zizmor.yml@a4723c4cafe1eaac7d9e985b5a47b1c2bdd821a5
     with:
       runs-on: ${{ !github.event.repository.private && 'ubuntu-latest' || 'ubuntu-arm64-small' }}
       fail-severity: high