Locked file in Windows determinism test

[agocke]

Failure looks like

CSC : error CS0016: Could not write to output file 'D:\j\workspace\windows_deter---2fa6dcc1\Binaries\Obj\TestUtilities\Debug\Roslyn.Test.Utilities.xml' -- 'The process cannot access the file 'D:\j\workspace\windows_deter---2fa6dcc1\Binaries\Obj\TestUtilities\Debug\Roslyn.Test.Utilities.xml' because it is being used by another process.' [D:\j\workspace\windows_deter---2fa6dcc1\src\Test\Utilities\Portable\TestUtilities.csproj]

[agocke]

@jaredpar Could this be caused by multi-targeting? It looks like there's no TFM prefix in the Obj directory so I could see us attempting to write to the same XML file twice...

[tmat]

@agocke Dup of #21421

[tmat]

And yes, TFM needs to be in the path.

[jaredpar]

Looks like it may be this sdk issue

dotnet/sdk#475

[agocke]

Closing as dup