[Coroutines] Special handle __builtin_coro_resume for final_suspend nothrow check

Summary:
In https://reviews.llvm.org/D82029 we added the conformance check that the expression co_await promise.final_suspend() should not potentially throw.
As part of this expression, in cases when the await_suspend() method of the final suspend awaiter returns a handle, __builtin_coro_resume could be called on the handle to immediately resume that coroutine.
__builtin_coro_resume is not declared with noexcept and it shouldn't. We need to special check this case here.

Reviewers: modocache, lewissbaker, junparser

Reviewed By: lewissbaker

Subscribers: modocache, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82415