doctests still fail with No module named 'test.support'

[s-t-e-v-e-n-k]

Related to #6 , the doctests still fail with the similar error:

[   13s] platform linux -- Python 3.10.14, pytest-8.3.3, pluggy-1.5.0 -- /usr/bin/python3.10
[   13s] cachedir: .pytest_cache
[   13s] rootdir: /home/abuild/rpmbuild/BUILD/jaraco_test-5.5.1
[   13s] configfile: pytest.ini
[   13s] plugins: jaraco.test-5.5.1, typeguard-0.0.0
[   13s] collecting ... collected 5 items
[   13s]
[   13s] jaraco/test/__init__.py::test.property_error PASSED                      [ 20%]
[   13s] jaraco/test/cpython.py::test.cpython FAILED                              [ 40%]
[   13s] jaraco/test/cpython.py::test.cpython.from_test_support FAILED            [ 60%]
[   13s] tests/test_http.py::test_needs_internet SKIPPED (Internet connectivity
[   13s] unavailable)                                                             [ 80%]
[   13s] tests/test_http.py::test_network_marker SKIPPED (Internet connectivity
[   13s] unavailable)                                                             [100%]
[   13s]
[   13s] =================================== FAILURES ===================================
[   13s] ____________________________ [doctest] test.cpython ____________________________
[   13s] 001
[   13s] 002 Compatibility shims for getting stuff from test.support across
[   13s] 003 Python versions (for compatibility with Python 3.9 and earlier).
[   13s] 004
[   13s] 005 >>> os_helper = try_import('os_helper') or from_test_support('temp_dir')
[   13s] UNEXPECTED EXCEPTION: ModuleNotFoundError("No module named 'test.support'")
[   13s] Traceback (most recent call last):
[   13s]   File "/usr/lib64/python3.10/doctest.py", line 1350, in __run
[   13s]     exec(compile(example.source, filename, "single",
[   13s]   File "<doctest test.cpython[0]>", line 1, in <module>
[   13s]   File "/home/abuild/rpmbuild/BUILD/jaraco_test-5.5.1/jaraco/test/cpython.py", line 27, in from_test_support
[   13s]     import test.support
[   13s] ModuleNotFoundError: No module named 'test.support'
[   13s] /home/abuild/rpmbuild/BUILD/jaraco_test-5.5.1/jaraco/test/cpython.py:5: UnexpectedException