Remove old-style classes from tests

[sobolevn]

There are some cases inside tests when old-style classes are used together with new-style classes.
I think these cases should be removed, because there are no old-style classes anymore and we just have useless logic duplication in tests.

I've found several cases:

• cpython/Lib/test/test_descr.py

  Lines 3264 to 3265 in 57be545

  	class OldClass:
  	__doc__ = DocDescr()

• cpython/Lib/test/test_unicode.py

  Lines 2379 to 2385 in 57be545

  	class s1:
  	def __repr__(self):
  	return '\\n'
  	class s2:
  	def __repr__(self):
  	return '\\n'

  (it is actually duplicated after u prefix removal, but is very similar and should also be removed)

• cpython/Lib/test/pydocfodder.py

  Lines 83 to 120 in 57be545

  	class A_new(object):
  	"A new-style class."
  	def A_method(self):
  	"Method defined in A."
  	def AB_method(self):
  	"Method defined in A and B."
  	def AC_method(self):
  	"Method defined in A and C."
  	def AD_method(self):
  	"Method defined in A and D."
  	def ABC_method(self):
  	"Method defined in A, B and C."
  	def ABD_method(self):
  	"Method defined in A, B and D."
  	def ACD_method(self):
  	"Method defined in A, C and D."
  	def ABCD_method(self):
  	"Method defined in A, B, C and D."
  	def A_classmethod(cls, x):
  	"A class method defined in A."
  	A_classmethod = classmethod(A_classmethod)
  	def A_staticmethod():
  	"A static method defined in A."
  	A_staticmethod = staticmethod(A_staticmethod)
  	def _getx(self):
  	"A property getter function."
  	def _setx(self, value):
  	"A property setter function."
  	def _delx(self):
  	"A property deleter function."
  	A_property = property(fdel=_delx, fget=_getx, fset=_setx,
  	doc="A sample property defined in A.")
  	A_int_alias = int

• cpython/Lib/test/test_copy.py

  Lines 91 to 103 in 57be545

  	class Classic:
  	pass
  	class NewStyle(object):
  	pass
  	def f():
  	pass
  	class WithMetaclass(metaclass=abc.ABCMeta):
  	pass
  	tests = [None, ..., NotImplemented,
  	42, 2**100, 3.14, True, False, 1j,
  	"hello", "hello\u1234", f.__code__,
  	b"world", bytes(range(256)), range(10), slice(1, 10, 2),
  	NewStyle, Classic, max, WithMetaclass, property()]

• cpython/Lib/test/test_copy.py

  Lines 353 to 361 in 57be545

  	class Classic:
  	pass
  	class NewStyle(object):
  	pass
  	def f():
  	pass
  	tests = [None, 42, 2**100, 3.14, True, False, 1j,
  	"hello", "hello\u1234", f.__code__,
  	NewStyle, range(10), Classic, max, property()]

• cpython/Lib/test/test_gc.py

  Lines 546 to 547 in 57be545

  	# boom__new and boom2_new are exactly like boom and boom2, except use
  	# new-style classes.

• cpython/Lib/test/dtracedata/instance.py

  Lines 3 to 6 in 57be545

  	class old_style_class():
  	pass
  	class new_style_class(object):
  	pass

  (we should probably keep this one, because it tests more complex mechanics than one class possibly can)

I will send a PR.

• PR: gh-99430: Remove duplicated tests for old-styled classes #99432

• PR: [3.11] gh-99430: Remove duplicated tests for old-styled classes (GH-99432) #115298