ci(deps): bump actions/attest-build-provenance from 1 to 2 (#64)

Bumps [actions/attest-build-provenance](https://github.com/actions/attest-build-provenance) from 1 to 2.
- [Release notes](https://github.com/actions/attest-build-provenance/releases)
- [Changelog](https://github.com/actions/attest-build-provenance/blob/main/RELEASE.md)
- [Commits](actions/attest-build-provenance@v1...v2)

---
updated-dependencies:
- dependency-name: actions/attest-build-provenance
  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/release-plz.yml

@@ -34,7 +34,7 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.RELEASE_PLZ_PAT }}
           CARGO_REGISTRY_TOKEN: ${{ secrets.CARGO_REGISTRY_TOKEN }}
 
-      - uses: actions/attest-build-provenance@v1
+      - uses: actions/attest-build-provenance@v2
         with:
           subject-path: ${{ github.workspace }}/target/release/backup-deduplicator
         continue-on-error: true