Unify Xstream behavior with LogMiner when using DBMS_LOB methods

In DBZ-4366, LogMiner adapter was adjusted to emit multiple DBSM_LOB method calls to methods such as APPEND as a single event rather than individual events. This allows the consumer to receive the data for LOB package methods as a single event.

Unfortunately, Xstream emits these as separate events. We've documented that this is a nuanced behavior of Xstream currently but would like to look into how to unify the behavior and avoid this nuance if possible.