GH-110109: Move tests for pathlib ABCs to new module. (#112904)

Author: barneygale

Lib/test/test_pathlib/__init__.py

@@ -0,0 +1,5 @@
+import os
+from test.support import load_package_tests
+
+def load_tests(*args):
+    return load_package_tests(os.path.dirname(__file__), *args)