maint: bump actions/labeler from 5 to 6 (#640)

Bumps [actions/labeler](https://github.com/actions/labeler) from 5 to 6.
- [Release notes](https://github.com/actions/labeler/releases)
- [Commits](actions/labeler@v5...v6)

---
updated-dependencies:
- dependency-name: actions/labeler
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/labeler.yml

@@ -29,7 +29,7 @@ jobs:
 
     # Label based on modified files
     - name: Label based on changed files
-      uses: actions/labeler@v5
+      uses: actions/labeler@v6
       with:
         repo-token: "${{ secrets.GITHUB_TOKEN }}"