SOLR-16470: Include IOException in logs when DirectoryFileStream fails

[jkmuriithi]

https://issues.apache.org/jira/browse/SOLR-16470

Description

I've been looking at the SolrCloud replication process a lot recently (for this dev list thread), and I noticed that Solr doesn't log the IOException which is thrown when the shard leader fails to write the response. I've linked the Jira ticket from when this API was last modified.

Solution

Made a one-line change to add the IOException to the logs.

Tests

Didn't feel like it was necessary to add new tests. Existing tests all pass.

Checklist

Please review the following and check all that apply:

• I have reviewed the guidelines for How to Contribute and my code conforms to the standards described there to the best of my ability.
• I have created a Jira issue and added the issue ID to my pull request title.
• I have given Solr maintainers access to contribute to my PR branch. (optional but recommended, not available for branches on forks living under an organisation)
• I have developed this patch against the main branch.
• I have run ./gradlew check.
• I have added tests for my changes.
• I have added documentation for the Reference Guide

[jkmuriithi]

@mlbiscoc You're probably the best equipped to take a look at this, since you made the original PR.

[mlbiscoc]

Thanks Jude for adding this. Could you also update here as well?

@gerlowskija SOLR-16470 was from a migration v2 migration. Do we still need CHANGES.txt entry for small changes like this and do we still want to reference the old SOLR-16470 v2 Jira for this PR?