wip: BuildKit cache dance

Author: featherbread

.github/workflows/build-image.yaml

@@ -7,6 +7,15 @@ jobs:
     steps:
     - name: Set up Docker Buildx
       uses: docker/setup-buildx-action@v3
+    - name: Configure BuildKit cache
+      uses: actions/cache@v4
+      id: buildkit-cache
+      with:
+        path: buildkit-cache-mount
+    - name: Inject BuildKit cache
+      uses: reproducible-containers/buildkit-cache-dance:6f699a72a59e4252f05a7435430009b77e25fe06
+      with:
+        cache-dir: buildkit-cache-mount
     - name: Build Image
       uses: docker/build-push-action@v5
       with: