DXCDT-218: Allow empty fields through pointers

[willvedd]

Description

There are some fields that are unable to be explicitly set to empty when making requests. This occurs with fields that are tagged with omitempty in their struct definitions; the system has no way to differentiate between explicitly empty and omitted. This shortcoming has been frequently logged as an issue in the Terraform provider repo, cataloged here. This PR attempts to completely rectify this inability by setting the field types to pointers. By doing so, we introduce a tertiary state that we can use to distinguish between omitted and explicitly empty values.

⚠️ Note: These changes introduce breaking changes! However, the intention is for this to be one of the last breaking changes before v1.

References

• Related issue in auth0/terraform-provider-auth0

Testing

• This change adds test coverage for new/changed/fixed functionality

Checklist

• I have read and agreed to the terms within the Auth0 Code of Conduct.
• I have read the Auth0 General Contribution Guidelines.
• I have reviewed my own code beforehand.
• I have added documentation for new/changed functionality in this PR.
• All active GitHub checks for tests, formatting, and security are passing.
• The correct base branch is being used, if not main.