build(deps): bump docker/build-push-action from 6 to 7 (#395)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 6 to 7.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v6...v7)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Author: dependabot[bot]

.github/workflows/publish.yaml

@@ -66,7 +66,7 @@ jobs:
         run: |
           echo "${{ secrets.GITHUB_TOKEN }}" | cosign login -u ${{ github.repository_owner }} --password-stdin ghcr.io
       - name: Build images and push
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           file: ${{ matrix.file }}
           platforms: ${{ matrix.platforms }}