[ava-check] upgrade ava, fix broken types for flow and ts

[bcherny]

Before, using ava-check in my project (with Ava 25) gave the following error:

node_modules/ava-check/ava-check.d.ts(5,26): error TS2305: Module '"/Users/bcherny/Sites/tsoption/node_modules/ava/types/generated"' has no exported member 'ContextualTestContext'.

And before, the ava-check build failed:

> flow check test

Error ┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ava-check.js.flow:4:15

Cannot import ValueGenerator because there is no ValueGenerator export in testcheck.

     1│ /* @flow */
     2│
     3│ export { gen } from 'testcheck'
     4│ import type { ValueGenerator, CheckOptions } from 'testcheck'
     5│
     6│ type Test<T> = (t: T) => void;
     7│


Error ┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ test/check.test.js:15:32

Could not decide which case to select. Since case 2 [1] may work but if it doesn't case 6 [2] looks promising too. To
fix add a type annotation to return [3].

     test/check.test.js
     12│   t.is(typeof x, 'number')
     13│ ))
     14│
 [3] 15│ test('generates with options', check({ numTests: 10 }, gen.posInt, (t, x) => {
     16│   t.true(x >= 0)
     17│ }))
     18│

     ava-check.js.flow
 [1] 13│   <T,A,B>(
     14│     genA: ValueGenerator<A>,
     15│     genB: ValueGenerator<B>,
     16│     f: (t: T, a: A, b: B) => boolean | void
     17│   ): Test<T>;
       :
 [2] 40│   <T,A>(
     41│     options: CheckOptions,
     42│     genA: ValueGenerator<A>,
     43│     f: (t: T, a: A) => boolean | void
     44│   ): Test<T>;


Warning ┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ test/types.js.flow:7:3

Unused suppression comment.

      4│ import { gen, check } from '../';
      5│
      6│ test('generates', check(gen.int, gen.string, (t, x, y) => {
      7│   // $ExpectError
      8│   t.true(x * y === 321)
      9│   //         ^ string. The operand of an arithmetic operation must be a number.
     10│ }))


Found 2 errors and 1 warning