sub-folders don't work for placing VMs

[soostdijck]

When the infra provider tries to find a folder it only works with a single folder (without a subfolder) or with a full path.

For example these work:
folder: "/mydatacenter/vm/Talos/dev"
folder: "Talos"

However I expect this to also work:
folder: "Talos/dev"

I suspect the code is running into this govmomi bug.
A workaround is needed in provider/provision.go around line 339. I would look into it, but I'm not savvy with go.