Optimize no rows only count

[risdenk]

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

Description

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Solution

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Tests

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Checklist

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• [ ] 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

[dsmiley]

(I didn't mean to un-DRAFT; I was fiddling with the IntelliJ integration)

[HoustonPutman]

@risdenk should we move forward with this?

[risdenk]

Probably I totally forgot about this