Add support for this ASDF plugin in Renovate

[MPV]

Hi,
Would you be up for (collaborating on) adding support for this plugin in Renovate?

What

Here's an example of how this is done (for other plugins):

• feat(asdf): Add support for more ASDF plugins renovatebot/renovate#21942

Why

So users of this plugin can benefit from Renovate (automated pull requests for version upgrades), i.e:

• https://www.mend.io/renovate/
• https://docs.renovatebot.com/