MINOR: doc change for minisr to clarify replicas in Kafka Config

[pdruley]

This is a minor doc change to MinInSyncReplicasDoc to clarify what is a replica and further help users understand the importance of this configuration in relation to their producer configuration.

It didn't seem like a Jira was necessary but I am open to creating one if needed. I did not compile from source to test, no other code was changed.

This contribution is my original work and I license the work to the project under the project's open source license.

Thanks!

Committer Checklist (excluded from commit message)

• Verify design and implementation
• Verify test coverage and CI build status
• Verify documentation (including upgrade notes)

[joel-hamill]

LGTM, had one comment

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[divijvaidya]

@pdruley can you please fix the conflict and we can work towards merging this PR.

[pdruley]

@pdruley can you please fix the conflict and we can work towards merging this PR.

I resolved the conflict but where are the docs for the configuration settings now?

[divijvaidya]

@pdruley can you please fix the conflict and we can work towards merging this PR.

I resolved the conflict but where are the docs for the configuration settings now?

Here:

kafka/server-common/src/main/java/org/apache/kafka/server/config/ServerLogConfigs.java

Line 138 in 40890fa

public static final String MIN_IN_SYNC_REPLICAS_DOC = "When a producer sets acks to \"all\" (or \"-1\"), " +