Consider all error codes on WT_CURSOR advancement before examining contents.

One example where get_key (within hasWrongPrefix) is called before checking errors codes that may not be WT_NOTFOUND:

https://github.com/mongodb/mongo/blob/ba0ee77c61c39b077d0975b7487099c5985c7b18/src/mongo/db/storage/wiredtiger/wiredtiger_record_store.cpp#L1716-L1720