Running tests fail

[jgarte]

Hi,

Do you happen to know why the following test might fail?

tly cleaning up <TemporaryDirectory '/tmp/guix-build-python-mkdocs-monorepo-plugin-1.0.4.drv-0/docs_ez27_kvk'>
  _warnings.warn(warn_message, ResourceWarning)
test_plugin_on_serve (mkdocs_monorepo_plugin.tests.test_plugin.TestMonorepoPlugin) ... ok
test_plugin_on_serve_no_run (mkdocs_monorepo_plugin.tests.test_plugin.TestMonorepoPlugin) ... ok

======================================================================
ERROR: test_plugin_on_config_with_nav (mkdocs_monorepo_plugin.tests.test_plugin.TestMonorepoPlugin)
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Traceback (most recent call last):
  File "/tmp/guix-build-python-mkdocs-monorepo-plugin-1.0.4.drv-0/mkdocs-monorepo-plugin-1.0.4/mkdocs_monorepo_plugin/tests/test_plugin.py", line 25, in test_plugin_on_config_with_nav
    plugin.on_config({
  File "/tmp/guix-build-python-mkdocs-monorepo-plugin-1.0.4.drv-0/mkdocs-monorepo-plugin-1.0.4/mkdocs_monorepo_plugin/plugin.py", line 52, in on_config
    new_docs_dir = self.merger.merge()
  File "/tmp/guix-build-python-mkdocs-monorepo-plugin-1.0.4.drv-0/mkdocs-monorepo-plugin-1.0.4/mkdocs_monorepo_plugin/merger.py", line 74, in merge
    raise SystemExit(1)
SystemExit: 1

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Ran 4 tests in 0.003s