Bump actions/github-script from 7 to 8 (#111716)

Bumps [actions/github-script](https://github.com/actions/github-script) from 7 to 8.
- [Release notes](https://github.com/actions/github-script/releases)
- [Commits](https://github.com/actions/github-script/compare/v7...v8)

---
updated-dependencies:
- dependency-name: actions/github-script
  dependency-version: '8'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/sync-mirror-event.yml

@@ -41,7 +41,7 @@ jobs:
           app_id: ${{ vars.DELIVERY_BOT_APP_ID }}
           private_key: ${{ env.GRAFANA_DELIVERY_BOT_APP_PEM }}
 
-      - uses: actions/github-script@v7
+      - uses: actions/github-script@v8
         if: github.repository == 'grafana/grafana'
         with:
           github-token: ${{ steps.generate_token.outputs.token }}