Update docker/setup-buildx-action digest to 4b4e9c3 (#101)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: Alexander Brandes <brandes.alexander@web.de>

.github/workflows/build.yml

@@ -7,9 +7,9 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@f03ac48505955848960e80bbb68046aa35c7b9e7 # v2
+        uses: docker/setup-buildx-action@v2
       - name: Build
-        uses: docker/build-push-action@3b5e8027fcad23fda98b2e3ac259d8d67585f671 # v4
+        uses: docker/build-push-action@v4
         with:
           context: .
           file: ./Dockerfile