Closes #2353 (closed).
Ubuntu complains with
ERROR 1064 (42000) at line 7: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'REQUIRE X509' at line 1. https://jenkins.aws.isc.org/view/Kea-manual/job/kea-manual/job/ut-extended/103/
The solution in this MR is to fallback to another command. At @fdupont's recommendation, let's try ALTER first, because it affects all tables.