restart method
This Method Restarts the Countdown Timer, Here optional int parameter duration is the updated duration for countdown timer
Implementation
void restart({int? duration}) {
_state._controller.duration =
Duration(seconds: duration ?? _state._controller.duration!.inSeconds);
if (_isReverse) {
_state._controller.reverse(from: 1);
} else {
_state._controller.forward(from: 0);
}
}