Fix issue in NamedPipeServerStream.GetImpersonationUserName() (#37676)

Fix issue in NamedPipeServerStream.GetImpersonationUserName() (#37676)

Fix for issue where NamedPipeServerStream.GetImpersonationUserName() throws unexpected InvalidationOperationException("The operation completed successfully") when impersonation is not allowed, when in fact it should simply return an empty string.

The fix will call GetNamedPipeHandleStateW once. If it fails, it will try to load sspicli.dll if it was not loaded, and will reattempt the call to GetNamedPipeHandleStateW.

This fix is only for Win32: UAP does not allow calling LoadLibraryEx, and Windows Nano says denies access to GetNamedPipeHandleStateW even after attempting to load sspicli.dll.

Signed-off-by: dotnet-bot <dotnet-bot@microsoft.com>