Bump docker/build-push-action from 3 to 6

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 3 to 6.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v3...v6)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/integration-testing.yml

@@ -44,7 +44,7 @@ jobs:
           echo "APP_IMAGE=public.ecr.aws/aws-otel-test/ruby-${{ matrix.app-platform }}-${{ matrix.instrumentation-type }}:${{ github.sha }}" |
           tee --append $GITHUB_ENV;
       - name: Build and Push Docker image
-        uses: docker/build-push-action@v3
+        uses: docker/build-push-action@v6
         with:
           push: true
           context: ${{ env.APP_PATH }}

.github/workflows/pr-build.yml

@@ -30,7 +30,7 @@ jobs:
           echo "APP_IMAGE=public.ecr.aws/aws-otel-test/ruby-${{ matrix.app-platform }}-${{ matrix.instrumentation-type }}:${{ github.sha }}" |
           tee --append $GITHUB_ENV;
       - name: Build Docker image
-        uses: docker/build-push-action@v3
+        uses: docker/build-push-action@v6
         with:
           context: ${{ env.APP_PATH }}
           tags: |