Enforce usage of @ts-expect-error over @ts-ignore

[mcmire]

Occasionally it is useful when converting a codebase to TypeScript to allow TypeScript errors, such as in this case for eth-ledger-bridge-keyring. The default configuration for the ban-ts-comment rule bans @ts-ignore and allows @ts-expect-error with a description. There's nothing wrong with this; however, I am not sure how many people know about this tag. I've seen people try to use @ts-ignore and then get around the lint violation by pairing it with an eslint-disable comment. While we can't prevent this, I think we can make the lint violation error more useful. I propose that we enable the prefer-ts-expect-error rule.