Bump dessant/lock-threads from 5.0.1 to 6.0.0 (#3639)

Bumps [dessant/lock-threads](https://github.com/dessant/lock-threads) from 5.0.1 to 6.0.0.
- [Release notes](https://github.com/dessant/lock-threads/releases)
- [Changelog](https://github.com/dessant/lock-threads/blob/main/CHANGELOG.md)
- [Commits](https://github.com/dessant/lock-threads/compare/v5.0.1...v6.0.0)

---
updated-dependencies:
- dependency-name: dessant/lock-threads
  dependency-version: 6.0.0
  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/lock.yml

@@ -13,7 +13,7 @@ jobs:
       issues: write  # for dessant/lock-threads to lock issues
     runs-on: ubuntu-latest
     steps:
-      - uses: dessant/lock-threads@v5.0.1
+      - uses: dessant/lock-threads@v6.0.0
         with:
           github-token: ${{ github.token }}
           issue-inactive-days: '90'