`dotnet test` no longer has test output for libraries projects

Steps to reproduce:

1. Build the runtime with `./build.sh -rc release -s clr+libs`
2. Attempt to run the tests for a test project from the command line: `./dotnet.sh test src/libraries/System.Security.Cryptography/tests`

## Behavior

MSBuild produces build output, but there is no output from Xunit.

## Expected Behavior

Xunit test results are printed

## Workarounds

`./dotnet.sh build /t:test` is not affected. `./dotnet.sh test` is.

Reproduce with `./build.sh -rc release -s clr+libs`, then run `./dotnet.sh test src/libraries/System.Security.Cryptography/tests` and compare it with `./dotnet.sh build /t:test`. Trace the `dotnet test` path for library test projects and verify that Xunit test results are printed while the unaffected workaround continues to work.

Written by the indexing model from the issue text.