cassandra: Add support for non-ASCII origin 'URLs'.
We agreed a while ago they are IRIs, and we have some of them in the postgresql database already.
Closes swh/infra/sysadm-environment#3394 (closed)
Test Plan
- New test for origins
-
test_add_arbitrary
will check it for other object types thanks to swh-model!191 (closed).
Migrated from D5932 (view on Phabricator)