Some test cases were working but for the wrong reasons. These started
to fail when I implemented the first approach for #4763, where the
existence of a DNSKEY together with an empty keyring is suspicious and
would prevent the keymgr from running.
These are:
1. kasp: The multisigner-model2.kasp zone has ZSKs from other providers
in the zone, but not yet its own keys. Pregenerate signing keys and
add them to the unsigned zone as well.
2. kasp: The dynamic-signed-inline-signing.kasp zone has a key generated
and added in the raw version of the zone. But the key file is stored
outside the key-directory for the given zone. Add '-K keys' to the
dnssec-keygen command.
(cherry picked from commit d1e263ef13)