No error is reported when an index creation fails

It can be related or duplicate to #56 I have a schema with the only partition key column, `site_id`. When I run the following command to creation of index from latte, no error is reported, however, it actually fails. The command: ``` db.execute(`CREATE CUSTOM INDEX IF NOT EXISTS ON ${KEYSPACE}.${TABLE}(site_id) USING 'StorageAttachedIndex'`).await?; ``` The expected error: ``` Cannot create secondary index on the only partition key column site_id ``` I can verify in the log of Cassandra that the index on `site_id` is not created, while other indexes are created.