test: refactor tests.test_section to use cxml
test: refactor tests.test_section to use cxml

SimplyAgree/python-docx,yurac/python-docx,eruffaldi/python-docx,holli-holzer/python-docx,tanyunshi/python-docx,python-openxml/python-docx,Nuos/python-docx,jean/python-docx,mohamedattahri/python-docx