Fastpath definition in schema.sql out of sync

[LDiazN]

The fastpath table definition in schema.sql is missing the anonymous credentials related fields, we should update it accordingly

See: https://github.com/ooni/backend/blob/52dbd4b935e86b357f1a9152df900f3092072399/ooniapi/services/ooniprobe/tests/fixtures/initdb/01-scheme.sql#L254-L258