Bump docker/setup-buildx-action from 1 to 2

Bumps [docker/setup-buildx-action](https://github.com/docker/setup-buildx-action) from 1 to 2.
- [Release notes](https://github.com/docker/setup-buildx-action/releases)
- [Commits](docker/setup-buildx-action@v1...v2)

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

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

.github/workflows/ci-docker.yaml

@@ -11,7 +11,7 @@ jobs:
         uses: actions/checkout@v2
       -
         name: "Set up Docker Buildx"
-        uses: docker/setup-buildx-action@v1
+        uses: docker/setup-buildx-action@v2
       -
         name: "Cache Docker layers"
         uses: actions/cache@v2.1.4