In the kasp system test, we are going to set the keytimes on
dnssec-keygen so we can test them against the key creation time.
This prevents off by one second in the test, something that can
happen if you set those times with dnssec-settime after
dnssec-keygen.
Also fix some test output filenames.
(cherry picked from commit 637d5f9a68)
34fd8a0531