Bump actions/attest-build-provenance from 2 to 4 (#89)

Bumps [actions/attest-build-provenance](https://github.com/actions/attest-build-provenance) from 2 to 4.
- [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@v2...v4)

---
updated-dependencies:
- dependency-name: actions/attest-build-provenance
  dependency-version: '4'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/docker-publish.yml

@@ -66,7 +66,7 @@ jobs:
             VERSION=${{ github.ref_name }}
 
       - name: Generate artifact attestation
-        uses: actions/attest-build-provenance@v2
+        uses: actions/attest-build-provenance@v4
         with:
           subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
           subject-digest: ${{ steps.push.outputs.digest }}