When testing that the impersonation proxy port was closed there
is no need to include credentials in the request. At the point when
we want to test that the impersonation proxy port is closed, it is
possible that we cannot perform a TokenCredentialRequest to get a
credential either.
Also add a new assertion that the TokenCredentialRequest stops handing
out credentials on clusters which have no successful strategies.
Signed-off-by: Monis Khan <mok@vmware.com>
1078bf4dfb