[CX] Secondary Index Entry Size Can Be Exceeded During Ingestion

We have a maximum allowed secondary index entry size (~64k). If an entry that exccedes that size exists during index creation, the index creation will fail with proper error message. However, if the index already exists and some document is encountered during ingestion causes the index to have an entry more than the allowed size, then ingestion is going to repeatedly fail in the background due to storage failure. We need to revisit the system behavior when this case in encountered.