Enhancement: On overrideNext or overrideBack only the widget should change not onTap.

[Dev-GauravKumar]

Is your feature request related to a problem? Please describe.
When i try to overrideNext or overrideBack then the onTap functionality also gets removed. instead of this only widget should change.

Describe the solution you'd like
We can change the code structure in next update so that it only change the visible widget not the onTap functionality. instead we can give override function for onTap of both widget.

Package version or git hash

• Version of IntroductionScreen 3.1.17

[flowhorn]

I think for these cases you could use the next property instead of overrideNext etc.

I added a PR which gives you the onPress-Logic for own Buttons:
#234