Creating host project fleet

[YpNo]

TL;DR

To be able creating an empty fleet on a project without creating a cluster

Terraform Resources

https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/gke_hub_fleet

Detailed design

Creating a fleet without anthos feature and without cluster creation should be possible. 
The terraform resource let configure Anthos parameters as well.

Additional information

No response