BAU: Bump docker/setup-buildx-action from 3.4.0 to 3.6.1

Bumps [docker/setup-buildx-action](https://github.com/docker/setup-buildx-action) from 3.4.0 to 3.6.1.
- [Release notes](https://github.com/docker/setup-buildx-action/releases)
- [Commits](docker/setup-buildx-action@4fd8129...988b5a0)

---
updated-dependencies:
- dependency-name: docker/setup-buildx-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/test-sidecar.yml

@@ -25,7 +25,7 @@ jobs:
       - name: Install dependencies
         run: yarn install
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@4fd812986e6c8c2a69e18311145f9371337f27d4 # v3.4.0
+        uses: docker/setup-buildx-action@988b5a0280414f521da01fcc63a27aeeb4b104db # v3.6.1
       - name: build sidecar container
         uses: docker/build-push-action@1ca370b3a9802c92e886402e0dd88098a2533b12 # v6.4.1
         with: