chore: Remove meaningless typeof undefined

[liuxingbaoyu]

Q	A
Fixed Issues?	Fixes #1, Fixes #2
Patch: Bug Fix?
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

#15379
I found in #15379 that typeof undefined is equivalent to any, which doesn't seem to make sense, let's remove them.

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/53835/

[ehoogeveen-medweb]

Yeah, I guess because undefined is a property of the global object, typeof undefined (in a position where a type is expected) is getting the type of that property, which is any or unknown. But undefined is also a primitive value and one of TypeScript's built-in types, so using undefined by itself does the right thing.