[DOC]Segment replication added consideration

[Poojita-Raj]

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• Request a change to existing documentation
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Tell us about your request. Provide a summary of the request and all versions that are affected.
https://opensearch.org/docs/latest/tuning-your-cluster/availability-and-recovery/segment-replication/index/#considerations
Under segment replication considerations, we want to add another consideration

7.  For segment replication -  Get, MultiGet, TermVector and MultiTermVector requests serve strong reads by routing requests to the primary shards. In a read heavy cluster (especially with listed request types), it is advisable to set the `realtime` parameter in these requests to `false`.

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.
opensearch-project/OpenSearch#8536
opensearch-project/OpenSearch#9212
opensearch-project/OpenSearch#9563