bpo-32964: Reuse a testing implementation of the path protocol in tests. (GH-5930)

(cherry picked from commit b21d155f57d284aecf9092a9bd24258293965c2f)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py
index 46cb5f1..ddee3b9 100644
--- a/Lib/test/test_subprocess.py
+++ b/Lib/test/test_subprocess.py
@@ -17,6 +17,7 @@
 import threading
 import gc
 import textwrap
+from test.support import FakePath
 
 try:
     import ctypes
@@ -359,12 +360,7 @@
     def test_cwd_with_pathlike(self):
         temp_dir = tempfile.gettempdir()
         temp_dir = self._normalize_cwd(temp_dir)
-
-        class _PathLikeObj:
-            def __fspath__(self):
-                return temp_dir
-
-        self._assert_cwd(temp_dir, sys.executable, cwd=_PathLikeObj())
+        self._assert_cwd(temp_dir, sys.executable, cwd=FakePath(temp_dir))
 
     @unittest.skipIf(mswindows, "pending resolution of issue #15533")
     def test_cwd_with_relative_arg(self):