gh-107178: Add the C API tests for the Abstract Objects Layer (GH-107179)

Cover all the Mapping Protocol, almost all the Sequence Protocol (except PySequence_Fast) and a part of the Object Protocol. Move existing tests to Lib/test/test_capi/test_abstract.py and Modules/_testcapi/abstract.c. Add also tests for PyDict C API.

Author: serhiy-storchaka

Lib/test/test_bytes.py

@@ -1354,7 +1354,7 @@ def do_tests(setitem):
  except ValueError:
  pass
  try:
- setitem(b, 0, None)
+ setitem(b, 0, object())
  self.fail("Didn't raise TypeError")
  except TypeError:
  pass