Allow named regions for vpshere cloud account

[attish76]

When creating a cloud account as below, the region name is the same as the externalRegionId.
This is different from what you get when creating the cloud account manually in the VRA UI, where the region name is <Folder>/<Datacenter name>

 resource "vra_cloud_account_vsphere" "vcs01" {
  name        = "vcs01.example.net"
  description = ""
  username    = var.username
  password    = var.password
  hostname    = "vcs01.example.net"
  regions     = ["Datacenter:datacenter-2001"]
  accept_self_signed_cert = true
}

[{'cloudAccountType': 'vsphere',
  'cloudAccountProperties': {'hostName': 'vcs01.example.net',
   'privateKeyId': '***',
   'supportTagging': '{"documentKinds":["com:vmware:photon:controller:model:resources:ComputeService:ComputeState"],"enabled":true}',
   'supportDatastores': 'true'},
  'enabledRegionIds': ['Datacenter:datacenter-2001'],
  'enabledRegions': [{'externalRegionId': 'Datacenter:datacenter-2001',
    'name': 'Datacenter:datacenter-2001',
  ...

However, both region emulation provides the DC name, and creating cloud accounts allows setting the region name

POST /iaas/api/cloud-accounts-vsphere/region-enumeration'
{
   'externalRegions': [
              {'externalRegionId': 'Datacenter:datacenter-2001', 'name': 'USA/DC01'}
  ]
'externalRegionIds': [
     'Datacenter:datacenter-2001'
]

POST /iaas/api/cloud-accounts-vsphere

  "regions": [
    {
      "name": "Datacenter:datacenter-3",
      "externalRegionId": "Datacenter:datacenter-3"
    }
  ],

Recommended solution

• Add new attribute externalRegions to data_source_vra_region_enumeration_vsphere
  This is map created from the externalRegions value of the region-enumration output, where key=name, value = externalRegionId.

• In resource_vra_cloud_account_vsphere, allow users to specify RegionSpecification themselves, instread of being generated by expandRegionSpecificationList
  

  terraform-provider-vra/vra/regions.go

  Line 31 in 120c582

  func expandRegionSpecificationList(rList []interface{}) []*models.RegionSpecification {