[CX] Connection recovery doesn't work when shadow dataset has a filter with functions

Assume the following DDLs:

CREATE BUCKET `bucket-1` WITH {"name":"bucket-1"};

CREATE SHADOW DATASET GleambookUsers ON `bucket-1` WHERE `id` is not UNKNOWN;

If something happened that caused the connection to break. For example bucket flush on KV or CBAS nodes restart, the connection is not restored correctly and the logs show NullPointerException.