Either add a new command or an addition `format` for structuring data for the Hub

I don't have strong opinions about what would be the best here, but either having an option so that users can output a YAML file for the Hub a la --about --format=hub, or if having a separate command --publish would work.

Goal is to output a YAML file similar to https://gitlab.com/meltano/hub/-/blob/main/_data/taps/3plcentral.yml for a given connector.

Of importance is the need for the variants key and structure so that's it's easy to either add as a variant or submit the whole defition.

• file would be the tap name with tap-
• YAML