gh-158856: Fix enum membership for values of a different hashability - #160576

Since #159250 made _hashable_values_ a set, value in EnumClass returns False for a value that equals a member value but has a different hashability. A set value is not found even for its own member: set.__contains__() looks up a set key as a frozenset instead of raising TypeError, so the list of unhashable values is never checked.

from enum import Enum
class Sets(Enum):
    A = {1, 2}
class Magic(Enum):
    PNG = b'\x89PNG'
Sets.A.value in Sets            # False, True on 3.14
frozenset({1, 2}) in Sets       # False, True on 3.14
bytearray(b'\x89PNG') in Magic  # False, True on 3.14

Check the unhashable values whenever the set lookup misses, and compare against the hashable values on TypeError. The regression is not in a release, so there is no NEWS entry.

• Issue: Enum creation is quadratic in the number of members (_hashable_values_ list scan) #158856