Bump docker/build-push-action from 5 to 6 (#246)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 5 to 6.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v5...v6)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  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>
Co-authored-by: Max Lambrecht <maxlambrecht@gmail.com>

Author: dependabot[bot]

.github/workflows/java-spiffe-helper-ci.yaml

@@ -32,7 +32,7 @@ jobs:
           distribution: 'temurin'
           java-version: '17'
       - name: Build container
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           tags: java-spiffe-helper:test

.github/workflows/release_build.yml

@@ -49,7 +49,7 @@ jobs:
       - name: Determine Docker Tag
         run: echo "DOCKER_TAG=${GITHUB_REF_NAME#v}" >> $GITHUB_ENV
       - name: Publish java-spiffe-helper Docker Image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           platforms: linux/amd64,linux/arm64