set ignore_unknown_options when parsing options (#13443)

set ignore_unknown_options when parsing options (#13443)

Summary:
In case the primary host has a new option added which isn't available in the remote worker yet, the remote compaction currently fails. In most cases, these new options are not relevant to the remote compaction and the worker should be able to move on by ignoring it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13443

Test Plan: Verified internally in Meta Infra.

Reviewed By: anand1976

Differential Revision: D70744359

Pulled By: jaykorean

fbshipit-source-id: eb6a388c2358a7f8089f2e35a378b7017b9e03f3