Time Picker of static mode is only updated when smallest unit of time is changed

[ruixuel]

Tech	Version
@material-ui/pickers	v4.0.0-alpha.8
material-ui	4.9.14
TypeScript	3.4.5
React	16.13.1
Browser
Peer library

Steps to reproduce

1. Render a static time picker as the demo: https://v4-0-0-alpha-8.material-ui-pickers.dev/demo/timepicker#static-mode
2. Change the hour in the picker
3. Click the edit icon (pen icon) in the picker
4. The hour is not changed at all. The onChange method is not called when change the hour in the picker.

Expected behavior

The hour should be changed

Actual behavior

The hour should be changed after the hour is changed in the picker

Live example

https://v4-0-0-alpha-8.material-ui-pickers.dev/demo/timepicker#static-mode

notes:
I also rendered the time picker with hour, minute and second. And the time picker will not call onChange() when hour and minute are changed in the picker. Not sure if this is by design, but I think user should be able to change any time unit and get the time updated.