* [ftr/visualize] continue to wait for save completion by default
* capture the toast message when saving the visualization so that it can be inspected if desired
* fix/flaky visualize listing tests (#33)
* move waitForSaveModalToClose from dashboard_page to common_page
* call common_page.waitForSaveModalToClose()
* remove extra wait for toast
* fix trailing spaces
* improve error message of failing test