Bump actions/attest-build-provenance from 1 to 2 (#226)

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>

Author: dependabot[bot]

.github/workflows/release.yml

@@ -31,6 +31,6 @@ jobs:
         args: release
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-    - uses: actions/attest-build-provenance@v1
+    - uses: actions/attest-build-provenance@v2
       with:
         subject-path: 'dist/checksums.txt'