Adjust plans printer for new supported engines

[christhemorse]

Description

This PR cleans up a few Managed Database Redis references and adjusts the plans printer to include Valkey/Kafka as supported engines and some engine-specific field adjustments: disk is hidden for Valkey plans just like in the API and VCPUs and RAM are hidden for Kafka.

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		coverage: 0.0% of statements

Pusher: @christhemorse, Action: pull_request_target

[optik-aper]

Looks good!