fix: ensure pytest ignores tests._lib

.github/workflows/python-test-ci.yml

@@ -21,7 +21,7 @@ jobs:
       run: |
         pip install pytest pytest-cov
         pip install --no-build-isolation --no-deps --disable-pip-version-check -e .
-        python -m pytest --doctest-modules --ignore=example
+        python -m pytest --doctest-modules --ignore=example --ignore=tests/_lib
         python -m doctest -v docs/*.md
     # name: Test examples
     # run: |
@@ -46,7 +46,7 @@ jobs:
         conda install -c /tmp/output/noarch/*.conda --update-deps --use-local dewret -y
         conda install pytest
         $CONDA/bin/pytest
-        python -m pytest --doctest-modules --ignore=example
+        python -m pytest --doctest-modules --ignore=example --ignore=tests/_lib
         python -m doctest -v docs/*.md
     # name: Test examples
     # run: |