Cupertino scrollbar can no longer be flung in flutter 2 #78688
Description
In the previous stable release of flutter (1.22.6) the cupertino scrollbar could be flung giving it some inertia just like the real scrollbar on iOS.
After the refactor done in #71664 this behavior was accidentally removed.
In pr #78689 I added a widget test for this behavior that passes on 1.22.6 and fails on the current master and stable channels