Summary:
- Unify where in the code tours get initiated.
- Avoid start a new tour while one is being started or is in progress.
- Ignore welcome tour when on a doc that has a doc tour.
- Fix tours when starting with a special page like Access Rules.
- Remove mention of the no-longer-present "Give Feedback" button in the last
message of the welcome tour.
Test Plan:
Add a browser test case that docTour preempts the welcome tour and shows no errors
(this test case fails in multiple ways without the changes).
Reviewers: georgegevoian
Reviewed By: georgegevoian
Differential Revision: https://phab.getgrist.com/D3330