Ensure typeIn has correct key option

[mydea]

Currently, the typeIn() helper will only set the charCode option of the KeyboardEvent. This PR also adds the correct key option.

[eliasmelgaco]

nice work

[rwjblue]

Hmm, I think we should use triggerKeyEvent's logic here, is there a way to refactor things into that?

[rwjblue]

@mydea - Have you had a chance to poke at my idea of reusing triggerKeyEvents logic?

[mydea]

I've pushed a commit making typeIn use triggerKeyEvent!

[rwjblue]

Looks like a small linting error is failing CI:

/home/travis/build/emberjs/ember-test-helpers/tests/unit/dom/type-in-test.js
  81:67  error  Delete `,`  prettier/prettier
✖ 1 problem (1 error, 0 warnings)
  1 error and 0 warnings potentially fixable with the `--fix` option.

[rwjblue]

The main changes here look good to me, thank you for working on it @mydea!

[mydea]

Oops, fixed it and also rebased on master!

[rwjblue]

FYI - We just realized (after a bit of digging with @trabus) that we accidentally made each key event triggering wait on settled with this update (totally my fault here though). Definitely not an intentional change, I think that @trabus is working up a PR to fix.