ipatests: fix test_ipahealthcheck.py::TestIpaHealthCheck
    
    test_ipa_healthcheck_expiring is assuming that it's executed
    on a KRA-less installation, but the test is executed after
    test_ipa_healthcheck_no_errors that configures the KRA.
    
    With a KRA install, 12 certs are monitored instead of 9.
    
    Fixes: https://pagure.io/freeipa/issue/8439
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>