Support MySQL Advanced Config

[christhemorse]

Description

This PR adds support for Managed Database MySQL advanced configuration options. It also provides a bug fix to the newer printer code that wasn't properly handling all of the different possible data types that could be set.

Checklist:

• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Have you linted your code locally prior to submission?
• Have you successfully ran tests with your changes locally?

[github-actions]

Unit Tests and Coverage

Show Output

?   	github.com/vultr/vultr-cli/v3	[no test files]

Pusher: @christhemorse, Action: pull_request_target

[optik-aper]

Good stuff!