Add resource provider registration resource

[hyperfocus1337]

PR Checklist

---

• I have added example(s) inside the [./examples/] folder
• I have added the example(s) to the integration test list for normal (~30 minutes) or long runner >30 minutes
• I have checked the coding conventions as per the wiki
• I have checked to ensure there aren't other open Pull Requests for the same update/change?

Description

This PR adds the Terraform azurerm_resource_provider_registration resource.

It includes examples for two features to enable, could be expand with more feature examples.

Does this introduce a breaking change

• YES
• NO

Testing

[arnaudlh]

LGTM

[arnaudlh]

thanks for your contribution @hyperfocus1337!