Bump actions/attest from 4.2.0 to 4.2.1

Bumps [actions/attest](https://github.com/actions/attest) from 4.2.0 to 4.2.1.
- [Release notes](https://github.com/actions/attest/releases)
- [Changelog](https://github.com/actions/attest/blob/main/RELEASE.md)
- [Commits](actions/attest@v4.2.0...v4.2.1)

---
updated-dependencies:
- dependency-name: actions/attest
  dependency-version: 4.2.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

.github/workflows/release.yml

@@ -30,6 +30,6 @@ jobs:
           args: release
         env:
           GITHUB_TOKEN: ${{ secrets.GORELEASER_GITHUB_ACCESS_TOKEN }}
-      - uses: actions/attest@v4.2.0
+      - uses: actions/attest@v4.2.1
         with:
           subject-checksums: ./dist/trellis_checksums.txt