API browser: Vertical scroll position resets when you click a class

**DocFX Version Used**:
2.30

**Template used**:
Tried both the default template and statictoc, neither works.

**Steps to Reproduce**:

Can be tested with the DocFX docs:

1. Go to any API documentation page with a lot of classes, e.g. [here](https://dotnet.github.io/docfx/api/Microsoft.DocAsCode.Metadata.ManagedReference.AttributeFilterInfo.html).
2. Scroll down on the left-hand side and select "YamlViewModelExtensions".
3. Note that the page opens fine, but the scrollbar on the left side has moved back to the top of the list.

**Expected Behavior**:
I expect the scroll bar position to remain where I put it. It's extra annoying when I'm trying to browse through multiple classes.

Sidenote: When I click a namespace, it moves the scrollbar as trees expand and contract. I noticed that I can click the plus-button next to them to avoid this, but I'd rather see this being the default behavior.

**Actual Behavior**:
See above.