Add metadata support for storage profile datasource

[adambarreiro]

Created by #372

:warn: Depends on vmware/go-vcloud-director#454

This PR adds metadata support (read) for the storage profile datasource. This was tested manually, as there is no vcd_storage_profile resource to manipulate metadata. The manual test is as follows:

• Go to the target VDC as System administrator, Provider view.
• Select a target storage profile
• Click on "Metadata" and add some string value.
• Execute a Terraform apply with the datasource. Metadata should have been retrieved.

[vbauzys]

could you check, maybe in config-gen we could use vpshere provider to add metadata in storage profile :)

[adambarreiro]

could you check, maybe in config-gen we could use vpshere provider to add metadata in storage profile :)

There seems to be a resource for storage policies: https://registry.terraform.io/providers/hashicorp/vsphere/latest/docs/resources/vm_storage_policy
But if we managed to create, still we'd need to add metadata through VCD.

[vbauzys]

could you check, maybe in config-gen we could use vpshere provider to add metadata in storage profile :)

There seems to be a resource for storage policies: https://registry.terraform.io/providers/hashicorp/vsphere/latest/docs/resources/vm_storage_policy But if we managed to create, still we'd need to add metadata through VCD.

Yes, you are right, even we could import resource we still add metadata on vpshere level, not VCD