Update docker/setup-buildx-action action to v4

| datasource  | package                    | from | to |
| ----------- | -------------------------- | ---- | -- |
| github-tags | docker/setup-buildx-action | v3   | v4 |


Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/ci.yaml

@@ -43,7 +43,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Login to GitHub Container Registry
         if: ${{ github.ref_name == 'main' }}
@@ -125,7 +125,7 @@ jobs:
 
     steps:
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Login to GitHub Container Registry
         uses: docker/login-action@v4