Bump actions/labeler from 5 to 7

Bumps [actions/labeler](https://github.com/actions/labeler) from 5 to 7.
- [Release notes](https://github.com/actions/labeler/releases)
- [Commits](https://github.com/actions/labeler/compare/v5...v7)

---
updated-dependencies:
- dependency-name: actions/labeler
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/auto_label_prs.yml

@@ -18,6 +18,6 @@ jobs:
     if: github.repository == 'velero-io/velero'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/labeler@v5
+      - uses: actions/labeler@v7
         with:
           configuration-path: .github/labeler.yml