Closes #22104: Merge with 3.4

diff --cc Misc/NEWS
index 864f894f93704a90113616a70fd03165c3d3f828,21b5ffa417022a82aaf6cac306da6a97d38aa5d9..f914cadc2fefb3ab0575d19a0024efaaf422cb38
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -802,49 -616,6 +802,52 @@@ Documentatio
  Tests
  -----
  
++- Issue #22104: regrtest.py no longer holds a reference to the suite of tests
++  loaded from test modules that don't define test_main().
++
 +- Issue #22111: Assorted cleanups in test_imaplib.  Patch by Milan Oberkirch.
 +
 +- Issue #22002: Added ``load_package_tests`` function to test.support and used
 +  it to implement/augment test discovery in test_asyncio, test_email,
 +  test_importlib, test_json, and test_tools.
 +
 +- Issue #21976: Fix test_ssl to accept LibreSSL version strings.  Thanks
 +  to William Orr.
 +
 +- Issue #21918: Converted test_tools from a module to a package containing
 +  separate test files for each tested script.
 +
 +- Issue #9554: Use modern unittest features in test_argparse. Initial patch by
 +  Denver Coneybeare and Radu Voicilas.
 +
 +- Issue #20155: Changed HTTP method names in failing tests in test_httpservers
 +  so that packet filtering software (specifically Windows Base Filtering Engine)
 +  does not interfere with the transaction semantics expected by the tests.
 +
 +- Issue #19493: Refactored the ctypes test package to skip tests explicitly
 +  rather than silently.
 +
 +- Issue #18492: All resources are now allowed when tests are not run by
 +  regrtest.py.
 +
 +- Issue #21634: Fix pystone micro-benchmark: use floor division instead of true
 +  division to benchmark integers instead of floating point numbers. Set pystone
 +  version to 1.2. Patch written by Lennart Regebro.
 +
 +- Issue #21605: Added tests for Tkinter images.
 +
 +- Issue #21493: Added test for ntpath.expanduser().  Original patch by
 +  Claudiu Popa.
 +
 +- Issue #19925: Added tests for the spwd module. Original patch by Vajrasky Kok.
 +
 +- Issue #21522: Added Tkinter tests for Listbox.itemconfigure(),
 +  PanedWindow.paneconfigure(), and Menu.entryconfigure().
 +
 +- Issue #17756: Fix test_code test when run from the installed location.
 +
 +- Issue #17752: Fix distutils tests when run from the installed location.
 +
  - Issue #18604: Consolidated checks for GUI availability.  All platforms now
    at least check whether Tk can be instantiated when the GUI resource is
    requested.