ci: bump docker/build-push-action from 4 to 5 (#6875)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 4 to 5.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](https://github.com/docker/build-push-action/compare/v4...v5)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  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>

.github/workflows/ci-outpost.yml

@@ -86,7 +86,7 @@ jobs:
       - name: Generate API
         run: make gen-client-go
       - name: Build Docker Image
-        uses: docker/build-push-action@v4
+        uses: docker/build-push-action@v5
         with:
           push: ${{ steps.ev.outputs.shouldBuild == 'true' }}
           tags: |