[require-await] require-await false positive

[mdouglass]

Repro

{
  "parser": "@typescript-eslint/parser",
  "parserOptions": { "project": "./tsconfig.json" },
  "plugins": ["@typescript-eslint"],
  "rules": {
    "@typescript-eslint/require-await": "error"
  }
}

async function testFunction(): Promise<void> {
  await Promise.all([1, 2, 3].map(async value => Promise.resolve(value)))
}

Expected Result
No warnings/errors

Actual Result
1:1 error Async function 'testFunction' has no 'await' expression @typescript-eslint/require-await

Additional Info
Changing the function passed to map to value => value causes the false positive to not trigger.

Versions

package	version
@typescript-eslint/eslint-plugin	2.6.1
@typescript-eslint/parser	2.6.1
TypeScript	3.7.2
ESLint	6.6.0
node	13.1.0
npm	6.12.1

[bradzacher]

It's a bug in the rule implementation.
The extension knows the inner callback doesn't need have an error, so it doesn't call the base rule's handler.
But in doing so, it means the base rule doesn't properly update its internal state, so it ends up looking at the state for the cb whilst exiting testFunction.