refactoring: review fixes

sbroad-cartridge/src/api/exec_query/protocol.rs

sbroad-cartridge/src/api/helper.rs

sbroad-cartridge/src/api/invalidate_cached_schema.rs

sbroad-cartridge/src/cartridge.rs

sbroad-cartridge/src/cartridge/router.rs

sbroad-cartridge/src/cartridge/storage.rs

sbroad-core/src/executor/engine.rs

sbroad-core/src/executor/engine/helpers.rs

sbroad-core/src/executor/protocol.rs