Bump actions/stale from 5 to 6 (#4245)

Bumps [actions/stale](https://github.com/actions/stale) from 5 to 6.
- [Release notes](https://github.com/actions/stale/releases)
- [Changelog](https://github.com/actions/stale/blob/main/CHANGELOG.md)
- [Commits](actions/stale@v5...v6)

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

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

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

.github/workflows/lifecycle_management.yml

@@ -9,7 +9,7 @@ jobs:
     if: github.repository == 'antrea-io/antrea'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v5
+      - uses: actions/stale@v6
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           stale-issue-message: 'This issue is stale because it has been open 90 days with no activity. Remove stale label or comment, or this will be closed in 90 days'