bpo-45878: convert `try/except` to `self.assertRaises` in `Lib/ctypes/test/test_functions.py` (GH-29721) (GH-29748)

(cherry picked from commit b48ac6fe38b2fca9963b097c04cdecfc6083104e)

Co-authored-by: Nikita Sobolev <mail@sobolevn.me>