Fix more tests missing 'it' call in 'describe'

[jakebailey]

I found more of these while debugging the parser. describe calls need to have an it call in them, otherwise all of that code runs before the tests are filtered, e.g. when debugging or running a single test, which is super annoying.

I tried adding --fail-zero to our mocha thing, but it doesn't seem to catch this because it was only designed to catch when you accidentally remove every test, not when a "suite" is missing any tests. Feels like this is worth a lint rule.