single_column_relation: Correctly print IN relation
single_column_relation: Correctly print IN relation

So that the output of a set of relations can be fed back into the CQL
parser; useful for materialized views.

Signed-off-by: Duarte Nunes <a60e8b7496f7715d71354fe4c06dd24017025bf1@scylladb.com>

avikivity/scylla,scylladb/scylla,duarten/scylla,scylladb/scylla,duarten/scylla,duarten/scylla,avikivity/scylla,scylladb/scylla,avikivity/scylla,scylladb/scylla