parameterization doesn't work for helm deployer

### Information
see integration/testdata/helm-namespace project as an example. Most likely, this is caused by schema adjustment where we copy helm deployer config to manifest.helm node if the node is not set.

### Expected behavior
- ``skaffold render --set replicaCount=3`` should set replicas value to 3 in the output manifest

### Actual behavior
- the result is still 2.