[3.12] pythongh-111881: Use lazy import in test.support (python#111885)…

… (python#111890)

pythongh-111881: Use lazy import in test.support (python#111885)

* Import lazily getpass in test.support

Backport to 3.11: test.support.os_helper is unchanged.

(cherry picked from commit 0372e3b)
(cherry picked from commit e983ca8)

Lib/test/support/__init__.py

@@ -6,7 +6,6 @@
 import contextlib
 import dataclasses
 import functools
-import getpass
 import os
 import re
 import stat
@@ -380,6 +379,7 @@ def wrapper(*args, **kw):
 
 def skip_if_buildbot(reason=None):
     """Decorator raising SkipTest if running on a buildbot."""
+    import getpass
     if not reason:
         reason = 'not suitable for buildbots'
     try: