Fix DDL Validation and Management for MaterializedPostgreSQL

Fix DDL validation for MaterializedPostgreSQL. Fix setting materialized_postgresql_allow_automatic_update. Closes #29535. #33200 (Kseniia Sumarokova). Make sure unused replication slots are always removed. Found in #26952. #33187 (Kseniia Sumarokova). Fix MaterializedPostreSQL detach/attach (removing / adding to replication) tables with non-default schema. Found in #29535. #33179 (Kseniia Sumarokova). Fix DROP MaterializedPostgreSQL database. #33468 (Kseniia Sumarokova).