UI Builder section has a scrollbar in "Library" section, which is not needed

Steps to reproduce:

1. Create a project
2.  Go to Window menu and select UI Toolkit->UI Builder;
3. Find "Library" section, which is displayed below the "Hierarchy";
4. Fold up"Containers", "Controls" and "Numeric Fields" sections;
5. Observe right side of the "Library" section.

Actual result: Scrollbar is displayed even it is not needed.

Expected result: Scrollbar should be hidden (shouldn't be displayed as it is in the "Inspector" window". Added screenshot in the "Attachments" section.

 

Reproducible with: 2023.1.0a21, 2023.1.0b7, 2023.2.0a5.

Not reproducible with: 2020.3.46f1 , 2021.3.20f1, 2022.2.9f1.