GSSAPI extended tests broken due to error type loss

[enj]

#17073 broke the types of errors returned from pkg/oc/cli/cmd/login/loginoptions.go. This breaks how pkg/oc/cli/cmd/login/login.go handles unauthorized errors.

=== BEGIN TEST CASE ===
/run/os/gssapi-tests.sh:30: executing 'oc login' expecting failure and text 'Login failed \(401 Unauthorized\)'
FAILURE after 0.460s: /run/os/gssapi-tests.sh:30: executing 'oc login' expecting failure and text 'Login failed \(401 Unauthorized\)': the output content test failed
There was no output from the command.
Standard error from the command:
error: unhandled challenge - verify you have provided the correct host and port and that the server is currently running.
=== END TEST CASE ===