Bug
1841966 - Fix verifyOpenLinkInNewPrivateTabContextMenuOptionTest UI test r=aaronmt
- **verifyOpenLinkInNewPrivateTabContextMenuOptionTest** was quite flaky because the click on the "Switch" snackbar button wasn't properly performed.
- The **clickPageObject** function wasn't suitable to perform the click action on the snackbar buttons, because in case of failures it tried to refresh the page (the page refresh is never needed)
- Added a retry loop, to retry the click while the snackbar is still being displayed
- Also removed other redundant snackbar click actions from other robots.
✅ **verifyOpenLinkInNewPrivateTabContextMenuOptionTest** - successfully passed 200x on Firebase
✅ **All UI tests** - successfully passed 3x on Firebase
Differential Revision: https://phabricator.services.mozilla.com/
D207113