docker: remove cache

this is not really necessary now

.github/workflows/docker.yaml

@@ -53,13 +53,6 @@ jobs:
         registry: ghcr.io
         username: ${{ github.repository_owner }}
         password: ${{ secrets.GITHUB_TOKEN }}
-    - name: Cache Docker layers
-      uses: actions/cache@v3
-      with:
-        path: /tmp/.buildx-cache
-        key: ${{ runner.os }}-buildx-${{ github.sha }}
-        restore-keys: |
-          ${{ runner.os }}-buildx-
     - name: Build and push
       uses: docker/build-push-action@v4
       with:
@@ -68,5 +61,3 @@ jobs:
         tags: ${{ steps.docker_meta.outputs.tags }}
         labels: ${{ steps.docker_meta.outputs.labels }}
         platforms: linux/amd64,linux/arm64
-        cache-from: type=local,src=/tmp/.buildx-cache
-        cache-to: type=local,dest=/tmp/.buildx-cache,mode=max