Added line chart test, trying more things to combat brittle tests and improve debugging

...tend/src/metabase/components/AddToDashSelectDashModal.jsx

frontend/src/metabase/components/CreateDashboardModal.jsx

frontend/src/metabase/components/ModalContent.jsx

frontend/src/metabase/components/QuestionSavedModal.jsx

frontend/src/metabase/components/SaveQuestionModal.jsx

frontend/test/e2e/admin/datamodel.spec.js

frontend/test/e2e/admin/people.spec.js

frontend/test/e2e/query_builder/query_builder.spec.js

frontend/test/e2e/setup/signup.spec.js

frontend/test/e2e/support/utils.js