Inconsistent tooltips throughout AppUI

[GintV]

Is your feature request related to a problem? Please describe.

Tooltips are inconsistent throughout AppUI - somewhere itwinui tooltips are used (good), whereas somewhere there are still title attribute used. All tooltips in AppUI should use itwinui tooltips. This request came from our UX.

e.g. tools, pins tooltips are itwinui

but widget tabs tooltips arent

Describe the Solution you'd like

No response

Describe alternatives you've considered

No response

Additional context

No response

[GerardasB]

Re-opening the issue to track other title attribute usage.