`test_tkinter` fails on refleak run due to `support` confusion

[zware]

Bug report

When running the refleak test runner (-R), test_tkinter fails on the second run due to AttributeError: module 'test.test_tkinter.support' has no attribute 'load_package_tests'. This is because test_tkinter has its own support module, which when imported overwrites the support attribute set in Lib/test/test_tkinter/__init__.py. That module should instead import specific symbols from test.support and use them directly.

Your environment

• CPython versions tested on: main, 3.12
• Operating system and architecture: Windows, Linux, any other

Linked PRs

• gh-105077: Fix test_tkinter refleak checking #105078
• [3.12] gh-105077: Fix test_tkinter refleak checking (GH-105078) #105079

[erlend-aasland]

Resolved by:

• gh-105077: Fix test_tkinter refleak checking #105078
• [3.12] gh-105077: Fix test_tkinter refleak checking (GH-105078) #105079