Support for MigrateVm admin extension (I'll help)

[nutgood]

Is your feature request related to a problem? Please describe.

Yes, we need to programmatically migrate VMs and leverage the Go SDK a ton.

Describe the solution you'd like

There's at least one API call to implement:

POST /admin/extension/resourcePool/{id}/action/migrateVms

It looks like the SDK already has all the relevant types implement, except maybe the types required to make this call (which seems to only be MigrateParams.

I'm thinking we could implement this inside vsphere_resource_pool.go since this api call is on a given resource pool, but we're looking for guidance here.

Describe alternatives you've considered

No response

Additional context

We're open to driving the implementation for this, but are looking for guidance.