🐛 Flyout's close transition duration is different

[harlanx]

Describe the bug
When passing a custom duration to transitionDuration in FlyoutContoller.showFlyout, it only gets applied to the animation when opening the flyout.

Screenshots

Duration.zero	Duration(seconds: 3)

[harlanx]

It might be the reverseTransitionDuration is not set and is using the default value Duration(milliseconds: 300) on the PageRouteBuilder used in the Flyout class.

[bdlukaa]

The documentation on both transition duration properties led me to think that I only needed to set one. It is ambiguous.

(love your UI btw)