fix: prevent incorrect range queries when searching for a page version

[avinassh]

It is important to verify that the data we got from Foundation DB matches with what we want, since we are doing a range query.

for example, say we searched for ('db_name42', 10, 20). If this page does not exist, then it could match with ('db_name41', 10, 20) or with ('db_name42', 9, 20) since it does lexicographic search.

[avinassh]

is there a way to prevent fetching a page we are not interested in?

This query is checking index only for the right frame number for the page. It does not fetch the frame.