Adding a test to check, and implementing the fix

[Paultagoras]

Summary

Turns out we were handling BigInteger in BigEndian format rather than LE - the test needed to be adjusted slightly to trigger the error properly.

Checklist

Delete items not relevant to your PR:

• Unit and integration tests covering the common scenarios were added
• A human-readable description of the changes was provided to include in CHANGELOG
• For significant changes, documentation in https://github.com/ClickHouse/clickhouse-docs was updated with further explanations or tutorials