fix: manually install docker buildx plugin

.gitea/workflows/build.yml

@@ -118,7 +118,10 @@ jobs:
 
       - name: Set up Docker Buildx
         run: |
-          apk add --no-cache docker-cli docker-cli-compose docker-buildx
+          apk add --no-cache docker-cli docker-cli-compose
+          mkdir -p ~/.docker/cli-plugins
+          curl -SL https://github.com/docker/buildx/releases/download/v0.14.1/buildx-v0.14.1.linux-amd64 -o ~/.docker/cli-plugins/docker-buildx
+          chmod +x ~/.docker/cli-plugins/docker-buildx
 
       - name: Login to registry
         run: echo "${{ secrets.REG_TOKEN }}" | docker login "${{ secrets.REGISTRY }}" -u "${{ secrets.REG_USER }}" --password-stdin