Support rubocop-sorbet alongside rubocop-airbnb

[bmulholland]

Now that typechecking is coming in Ruby 3, sorbet will likely become more popular. https://github.com/shopify/rubocop-sorbet has some rubocop rules for sorbet that would be great to include.

[britneywright]

@bmulholland Which version of rubocop are you using? sorbet is in supported in rubocop-0-92
See #261

[bmulholland]

Huh, I definitely searched for sorbet in this repo before filing the issue. Not sure how I missed that!

In any case, I'm unfortunately using the airbnb channel. Would you accept a PR to add sorbet to that channel?

[britneywright]

You can try opening a PR. Keep in mind the airbnb plugin has some strict dependencies (https://rubygems.org/gems/rubocop-airbnb) that may make compatibility with other plugins difficult. That's why we had to make a separate channel to support it.

[bmulholland]

Yeah, great point. I upgraded gems on the rubocop-airbnb gem and submitted a PR - let's see if that unblocks things here.