Could not find test (no symbols found) for tests inside classes inside class

I'd like to ask if there's a way to fix this one:

I usually write my tests in this format (this is very helpful for me for classes with lots of tests inside it):

```csharp
public class MyServiceTests
{
public class On_MethodCall()
{
[Fact]
public void Should_BlahBlah()
{
...
}
}
}
```

Everything is working great however when I try to click the test on the Test Explorer UI, I get a warning:

`Could not find test (no symbols found)`

I'd like to ask if this is a known issue or is there something that can be done to have this fixed?

Thanks!

Start by reproducing the warning in the Test Explorer UI with the nested test structure shown in the issue. Trace how the extension resolves a selected test to its symbols; done means clicking a test inside the nested classes opens it without the “Could not find test (no symbols found)” warning.

Written by the indexing model from the issue text.