Clean up `threw` assertions

[GoodForOneFare]

We still have assert.okay(foo.threw, 'error message')-style assertions. These should probably be converted to assert.fail('error message';), or the original CoffeeScript should be altered to not use this pattern.

[GoodForOneFare]

I looked into this, and it's probably easier to manually change stuff like

try
  foo();

assert.okay(foo.threw, 'error message')

to

try
   foo();
   assert.fail('error message')

[lemonmade]

Do you have a list of places where this appears in code? Is this something we can lint for?

[GoodForOneFare]

details_form_test.coffee (1 instance), state_test.coffee (3 instances), state_next_test.coffee. Definitely easier to fix manually because a couple of these have logic between the try and threw assertion.

Yes, we could lint for this. It could be added to #79, or be a new issue.

[lemonmade]

Let's do a new issue for the linting rule. I'll tackle updating those instances.

[lemonmade]

Let's set this aside for now. This is basically discussing a new rule (prefer trying and failing rather than assert.threw), which we can easily update to later on.