cherrypick #8768

This is a patch to release-7.1 after resolving conflicts from commit in main branch, in order to enable byteLimit in release-7.1

A fraction of byteLimit will be used as the limit to fetch index. For the indexes fetched, fetch records for them in batch.

byteLimit always count the index size, it also count record if exist, it at least return 1 index-record entry and always include the last entry despite that adding the last entry despite it might exceed limit.

There is a Knob STRICTLY_ENFORCE_BYTE_LIMIT, when it is set, records will be discarded once the byteLimit is hit, despite they are fetched. Otherwise, return the whole batch.

20221111-235132-haofu-8958e121461c599f

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