[FieldDefinitions] Support for Sorbet, heredoc descriptions, and shared resolver methods

[alex4787]

A few extensions were added to the FieldDefinitions to adapt to some issues we encountered linting the codebase at Shopify, namely:

• Support for Sorbet method signatures
• Support for field definitions with heredoc descriptions
• Support for when multiple fields share the same resolver method

I've amalgamated all the changes here as a work-in-progress PR, but before proceeding, I'd like to see if some/all of these are changes that you'd like to see in this gem. Once that's determined, I can break this down into more easily reviewable PRs and make appropriate updates.

[DmitryTsepelev]

Hi @alex4787, thanks for the proposal! I'm definitely open to any proposals since all cops are optional and users can easily turn off ones they don't like 🙂 Can't wait to merge this stuff in!

[alex4787]

@DmitryTsepelev Code should be good to merge now, I've split it into three commits (per feature):

• 78fa4c9 (Sorbet)
• e11b9fb (heredoc descriptions)
• e95a00a (multiple fields sharing resolvers)

Let me know if there's anything I should fix, or if it'd be better for these to be split into their own PRs.

[alex4787]

Some newline differences for autocorrection of FieldDefinitions because of how autocorrect is performed.

[DmitryTsepelev]

That's impressive, Thank you so much for the hard work! I'm going to merge it in and release the new version right now

[alex4787]

No problem! Thank you for being so open to these new additions and the quick responses, appreciate it! We'll be bumping our rubocop-graphql version very shortly for our codebase here 😄