Summary:
Recent refactor of `ReactiveVersionSet::ReadAndApply()` uses
`ManifestTailer` whose `Iterate()` method can cause the db's
`last_sequence_` to go backward. Consequently, read requests can see
out-dated data. For example, latest changes to the primary will not be
seen on the secondary even after a `TryCatchUpWithPrimary()` if no new
write batches are read from the WALs and no new MANIFEST entries are
read from the MANIFEST.

Fix the bug so that `VersionEditHandler::CheckIterationResult` will
never decrease `last_sequence_`, `last_allocated_sequence_` and
`last_published_sequence_`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8653

Test Plan: make check

Reviewed By: jay-zhuang

Differential Revision: D30272084

Pulled By: riversand963

fbshipit-source-id: c6a49c534b2509b93ef62d8936ed0acd5b860eaa