Update docker/setup-buildx-action action to v4 (#1047)

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

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

Author: renovate[bot]

.github/workflows/ci.yml

@@ -62,7 +62,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Build binary
         uses: docker/build-push-action@v6

.github/workflows/docker-openresty.yml

@@ -28,7 +28,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
         with:
           driver-opts: network=host
 

.github/workflows/docker.yml

@@ -43,7 +43,7 @@ jobs:
         uses: docker/setup-qemu-action@v3
 
       - name: Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
         with:
           driver-opts: network=host
 

.github/workflows/system-testing.yml

@@ -41,7 +41,7 @@ jobs:
         run: pip install -r test/requirements.ci.txt
 
       - name: Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Build nginx
         uses: docker/build-push-action@v6

.github/workflows/update-docker-images.yml

@@ -98,7 +98,7 @@ jobs:
         if: ${{ matrix.needs-updating == 'true' }}
 
       - name: Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
         if: ${{ matrix.needs-updating == 'true' }}
 
       - name: DockerHub Login