Update input styles

[srallen]

Package: lib-classifier

Describe your changes:
Gets the inputs to parity again with inputs in PFE (zooniverse/Panoptes-Front-End#5091). Bumps React version in order to use React.memo and refactors some of the tests because enzyme doesn't support React.memo yet.

The refactors of the styling reduces the manual handling of focus and blur and consequently speeds up the styling.

Review Checklist

General

• Are the tests passing locally and on Travis?
• Is the documentation up to date?
• Is the changelog updated?

Apps

• Does it work in all major browsers: Firefox, Chrome, Edge, Safari?
• Does it work on mobile?
• Can you rm -rf node_modules/ && npm install and app works as expected?

[srallen]

This just mirrors zooniverse/Panoptes-Front-End#5091 which is already approved.

[eatyourgreens]

I forgot that I’d removed the annotation prop in that PR, so there was a small follow-up PR too. zooniverse/Panoptes-Front-End#5104