tests: Fix non-blocking auth tests.
tests: Fix non-blocking auth tests.

The ssh_userauth_none() call should already be non-blocking. However
this this function is broken in non-blocking mode. It should reveal the
existing bug.

mwgoldsmith/libssh,mwgoldsmith/ssh,mwgoldsmith/libssh,mwgoldsmith/ssh,mwgoldsmith/libssh,mwgoldsmith/ssh,mwgoldsmith/libssh,mwgoldsmith/ssh