`pathlib` assumes that `functools` might not have `lru_cache`

[sobolevn]

There's this line in pathlib right now:

cpython/Lib/pathlib.py

Lines 218 to 219 in 018b248

	if hasattr(functools, "lru_cache"):
	_make_selector = functools.lru_cache()(_make_selector)

It was added 9 years ago as part of 31119e4

But, functools at this moment always has this function. It is widely used in other modules.

[AlexWaygood]

Fixed in #98885. Thanks @sobolevn!