fix: incorrect await rejection following arrow function in parameters (fixes #13872)

[The-x-Theorist]

Q	A
Fixed Issues?	Fixes #13872
Patch: Bug Fix?
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

When parsing an arrow expression, the error is raised when it reaches the stage where the function body is parsed and the expression scope is entered but never exited if the body is an expression.

[babel-bot]

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[nicolo-ribaudo]

Thanks for finding the problem! I'd prefer if we fixed this by moving the expressionScope.exit() call at line 2448 after the } that follows it, so that we keep an "one enter"-"one exit" correspondence in the code.

[The-x-Theorist]

Okay @nicolo-ribaudo I will change that.

[nicolo-ribaudo]

Could you also add a test for yield?

(function* () {
  function f(_=()=>null) {}
  yield;
});

[The-x-Theorist]

@nicolo-ribaudo Yeah, I will add test for yield too.