fixed duplicated method name of test_getuserbase() (GH-12140)

(cherry picked from commit 45d8d2469a48589e950dad2452043188eb9399a3)

Co-authored-by: native-api <ivan_pozdeev@mail.ru>
diff --git a/Lib/test/test_site.py b/Lib/test/test_site.py
index a30bd2f..655a12d 100644
--- a/Lib/test/test_site.py
+++ b/Lib/test/test_site.py
@@ -183,7 +183,9 @@
         finally:
             pth_file.cleanup()
 
-    def test_getuserbase(self):
+    # This tests _getuserbase, hence the double underline
+    # to distinguish from a test for getuserbase
+    def test__getuserbase(self):
         self.assertEqual(site._getuserbase(), sysconfig._getuserbase())
 
     def test_get_path(self):