Remove Clickhouse calls to get column data type for every batch insert

[subkanthi]

Currently there are 2 calls made before every batch is inserted to ClickHouse

• One to get the column data types
• One to get the list of alias/materialized columns.

The new logic should make the calls during startup and cache them.

• sink-connector-client call to refresh the Clickhouse cache.
• Make the calls only when there is an error during batch insertion.

[aadant]

Also when DDL is made on the table.