gh-93839: Move Lib/ctypes/test/ to Lib/test/test_ctypes/ (#94041)

* Move Lib/ctypes/test/ to Lib/test/test_ctypes/
* Remove Lib/test/test_ctypes.py
* Update imports and build system.

Author: vstinner

Lib/ctypes/test/__main__.py

@@ -1,5 +1,5 @@
 
-# Taken from Lib/ctypes/test/test_keeprefs.py, PointerToStructure.test().
+# Taken from Lib/test/test_ctypes/test_keeprefs.py, PointerToStructure.test().
 
 from ctypes import Structure, c_int, POINTER
 import gc

Lib/test/leakers/test_ctypes.py

@@ -0,0 +1,4 @@
+from test.test_ctypes import load_tests
+import unittest
+
+unittest.main()

Lib/test/test_ctypes.py

@@ -3,7 +3,7 @@
 import sys
 from ctypes import *
 
-from ctypes.test import need_symbol
+from test.test_ctypes import need_symbol
 
 formats = "bBhHiIlLqQfd"
 

Lib/ctypes/test/__init__.py renamed to Lib/test/test_ctypes/__init__.py

@@ -1,6 +1,6 @@
 import unittest
 from ctypes import *
-from ctypes.test import need_symbol
+from test.test_ctypes import need_symbol
 import _ctypes_test
 
 dll = CDLL(_ctypes_test.__file__)

Lib/test/test_ctypes/__main__.py

@@ -1,5 +1,5 @@
 from ctypes import *
-from ctypes.test import need_symbol
+from test.test_ctypes import need_symbol
 from test import support
 import unittest
 import os