When we use a custom patch that makes strong passwords required even for
administrators the check-kadmin test will fail because "foo" (the password
used in check-kadmin.in) is not a strong password. So, we make the
password used in check-kadmin.in settable as a parameter. This way, we
only have to change one line of check-kadmin.in rather than a dozen to get
check-kadmin to pass when using the strong-passwords everywhere patch.
Note that this change makes no real change to any of the tests in
check-kadmin.in: no tests are changed, removed, or added.