test: Fix TestIPA.testUnqualifiedUsers 2FA race condition
test: Fix TestIPA.testUnqualifiedUsers 2FA race condition

After configuring 2FA for a user, it takes a while to propagate to the
client. Wait until this happens, so that the Cockpit login will not use
the simple password authentication and time out waiting for the second
factor prompt.

cockpit-project/cockpit,mvollmer/cockpit,mvollmer/cockpit,cockpit-project/cockpit,mvollmer/cockpit,martinpitt/cockpit,cockpit-project/cockpit,mvollmer/cockpit,martinpitt/cockpit,martinpitt/cockpit,mvollmer/cockpit,martinpitt/cockpit,martinpitt/cockpit,cockpit-project/cockpit,cockpit-project/cockpit