Use correct last migration timestamp on schema
Current last migration is 20190222014121_remove_keywords_admin_only.rb but schema point to 20190222014120_add_subscriber_permissions.rb
This also fix flaky test on remove_keywords_admin_only_spec (cf https://0xacab.org/spk/schleuder/-/jobs/128996)
Fix #446 (closed)
Edited by Laurent Arnoud