Make Mouse Scroll Speed adjustable

[DarkPurpleKnight]

In the mouse settings, I noticed that in Deepin Linux, unlike in Windows 10, you cannot adjust the Mouse Scroll Speed.

In Windows 10 you can choose how many lines to scroll each time (see screenshot).

On Deepin Linux, there is no easy way to adjust the mouse scroll speed.

Steps to reproduce

1. Open Control Center
2. Click on Mouse in the left column.
3. Click on Mouse in the middle column.

Expected behaviour
A mouse scroll speed slider below the mouse acceleration slider.