use correct dockerfile for netclient

.github/workflows/test-artifacts.yml

@@ -58,6 +58,7 @@ jobs:
               with:
                   context: .
                   platforms: linux/amd64, linux/arm64
+                  file: ./docker/Dockerfile-netclient-multi-arch
                   push: true
                   tags: ghcr.io/gravitl/netclient:testing
                   build-args: version=testing