Try using loadscope pytest-xdist test distribution method to see if this

helps with a weird race we started to see more often with latest version
of pytest.

tox.ini

@@ -36,9 +36,9 @@ setenv =
 # NOTE: By default we run tests on CI in parallel to speed up the build
 # To avoid per-test function process safety issues we run all tests in a single
 # file in the same worker process.
-# for pytest-xdist, we want to distribute tests by file aka --dist loadfile
+# for pytest-xdist, we want to distribute tests by file (class + method) aka --dist loadscope
 commands = cp libcloud/test/secrets.py-dist libcloud/test/secrets.py
-           pytest --color=yes -rsx -vvv --capture=tee-sys -o log_cli=True --durations=10 --timeout=15 -n auto --dist loadfile --ignore libcloud/test/benchmarks/ --ignore-glob "*test_list_objects_filtering_performance*"
+           pytest --color=yes -rsx -vvv --capture=tee-sys -o log_cli=True --durations=10 --timeout=15 -n auto --dist loadscope --ignore libcloud/test/benchmarks/ --ignore-glob "*test_list_objects_filtering_performance*"
 
 [testenv:py3.8-dist]
 # Verify library installs without any dependencies when using python setup.py