fix(fill_db_data): don't run filter by NULL query for now
fix(fill_db_data): don't run filter by NULL query for now

This query is supported in 4.4 only meanwhile and fails on 4.2.
So all rolling upgrade tests fail.
We will run this query when will test 4.5

scylladb/scylla-cluster-tests,scylladb/scylla-cluster-tests,scylladb/scylla-cluster-tests,scylladb/scylla-cluster-tests,scylladb/scylla-longevity-tests,scylladb/scylla-longevity-tests,scylladb/scylla-cluster-tests,scylladb/scylla-longevity-tests