Use toast notification for positive feedback #3861
Description
Currently, we use different methods to confirm the success of some actions.
We wish to try having a single standard way of showing these notifications, and we picked Toasts (mind they should be independent from the legacy notifications object that also triggers toasts).
Examples of the feedback we are replacing:
- Green alert requiring some manual dismissal (E.G: additional step when creating a data connector or editing a session launcher)
- Green alert sticking around after a change (E.G. modify project settings)
- Notifications triggering an alert (E.G. delete a project)
- No feedback (E.G. create a project)