4.16 install state files not cleaned up

[afcollins]

Starting with 4.16 version tested today, there are additional local install state files that must be cleaned up.

Installer error message occurs on retry:

time="2024-07-09T20:18:28Z" level=fatal msg="failed to fetch Cluster: failed to load asset \"Cluster\": local infrastructure provisioning artifacts already exist. There may already be a running cluster"                                                                                             

I found the culprit in the installer code:

$INSTALL_DIR/.clusterapi_output/envtest.kubeconfig