Content under Secondary Textures window does not scroll up with mouse wheel instead Sprite editor window zooms out.

Steps to repro:
1. Create a new 2D Project.
2. Import a .png file and change the Texture Type to Sprite
3. Sprite Editor > Secondary Textures
4. Add Secondary Textures to the list till Vertical Scrollbar appears.
5. Move Mouse wheel up/down

Actual Result:
Vertical Scrollbar does not scroll up with the mouse wheel.

Expected Result:
Content under Secondary Textures window is scrolled with the mouse wheel.

Package found Version: 1.0.0

Tested with Unity version: 2020.1.0a17, 2019.3.0f3

Environment:
Windows 10 & macOS 10.14