Bump docker/build-push-action from 6 to 7

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
...

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

Author: dependabot[bot]

.github/workflows/docker.yml

@@ -59,7 +59,7 @@ jobs:
 
       - name: Build Docker image
         id: build
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           context: .
           load: true # load into docker instead of immediately pushing
@@ -72,7 +72,7 @@ jobs:
         run: docker run --rm -v $(pwd):/data ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ steps.meta.outputs.version }} /data/tests/regression/04-mutex/01-simple_rc.c # run image by version in case multiple tags
 
       - name: Push Docker image
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           context: .
           push: true