tests: cql_auth_query_test: de-template
tests: cql_auth_query_test: de-template

Replace the with_user() and verify_unauthorized_then_ok() templates with functions.
Some adjustments made to the call site to unify the signatures.

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