Description

Allow to clear the whole tasks inside a TaskGroup, instead of doing it one by one.

Use case / motivation

One of the things I love about SubDags is the option to clear the entire sub flow in case I want to rerun it.
In some cases I've a single parent and it's easy, but in some flows there are multiple parents (and now thanks to TaskGroup there could be even more easily), so the easy way to clear it is to go to the task instances page and start filtering, which is sub-optimal.

Are you willing to submit a PR?

Sure.