Update frontend to use the new StartAndDueDate extensions instead of rolled up widget

Context

With the goal to simplify the code around rolledup dates, we decided to unify (#470889 (closed)) StartAndDueDates and RolledupDates widgets in one. This way we'll have only StartAndDueDate widget where the rollup capabilities are an EE extension of that. Also, we simplify its interface, moving the whole rolleup logic to the backend.

The new GraphQL interface can is was implemented and is documented on #486526 (closed)

Proposed solution

Now with the simplified interface, we need to change the frontend to use only the StartAndDueDate fields and remove the deprecated RolledupDates component