Can't disable MSTEST0001 in project with no files

[gao-artur]

Describe the bug

The CSC : warning MSTEST0001: Explicitly enable or disable tests parallelization is reported even if dotnet_diagnostic.MSTEST0001.severity = none is configured in .globalconfig file if the test project has no content

Steps To Reproduce

1. Create a new test project from the template
2. Remove the MSTestSettings.cs and Test1.cs files
3. Create a .globalconfig file with the following content

is_global = true
dotnet_diagnostic.MSTEST0001.severity = none

4. Build the project

Expected behavior

No warnings from the compiler

Actual behavior

CSC : warning MSTEST0001: Explicitly enable or disable tests parallelization

Additional context

Adding any file, .cs or .txt or whatever, removes the warning.