Filters are no longer working in .Net Core 3.1

Windows (Microsoft visual studio 2019)

docfx.console 2.51.0

**Steps to Reproduce**:

1. Create a class library on .Net Core 3.1.
2. Create a public class and give it the `[EditorBrowsable(EditorBrowsableState.Never)]` attribute.
3. Install Nuget package docfx.console.
4. Build the project.

**Expected Behavior**:
The public class is not visible in the generated documentation.

**Actual Behavior**:
The public class is visible.

Switching the Target framework to .Net core 2.2 solves the problem. The class is no longer visible.
Creating a custom filter and excluding the class also doesn't work.