Tests: add docutils code origin reference

Author: jayaddison

tests/test_util/test_util_docutils_sphinx_directive.py

@@ -40,6 +40,7 @@ def make_directive_and_state(
     inliner.init_customizations(state.document.settings)
     state.inliner = inliner
     state.parent = None
+    # https://repo.or.cz/docutils.git/blob/2310dd9b468e9f86b00401b1aa60d47aabc199ac:/docutils/docutils/parsers/rst/states.py#l162
     state.memo = Struct(document=state.document,
                         reporter=state.document.reporter,
                         language=english,