If a certmonger CA is not defined but is referenced within
a request (so was removed sometime after a request was
created) then anything that pulls all certmonger requests would
fail with the cryptic error:
"Failed to get request: bus, object_path and dbus_interface
must not be None."
This was often seen during upgrades.
Catch this specific condition and report a more specific error
so the user will have some bread crumb to know how to address
the issue.
https://pagure.io/freeipa/issue/7870
Signed-off-by: Rob Crittenden <rcritten@redhat.com>
Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>