Fix flaky TPC-H Q15 floating-point assertion

[ahkcs]

Description

Updates the TPC-H Q15 integration test to use the existing ULP-aware MatcherUtils.closeTo(...) matcher for total_revenue.

The distributed sum() returned 797313.3838000001 in the failing release test instead of the exactly asserted 797313.3838. These values differ by one ULP, but rows(...) requires exact numeric equality. closeTo(...) tolerates platform-dependent floating-point rounding while continuing to compare the supplier ID and string fields exactly.

Related Issues

Resolves #5620

Testing

• ./gradlew :integ-test:spotlessJavaCheck :integ-test:compileTestJava --no-daemon
• ./gradlew :integ-test:integTest --tests "org.opensearch.sql.calcite.tpch.CalcitePPLTpchIT.testQ15" --no-daemon

Check List

• New functionality includes testing.
• New functionality has been documented.
• New functionality has javadoc added.
• New functionality has a user manual doc added.
• New PPL command checklist all confirmed.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff or -s.
• Public documentation issue/PR created.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-actions]

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[github-actions]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
General	Apply closeTo only to floating-point value The closeTo method is being used with mixed types (integers, strings, and a double), which may not be the intended usage. Consider using closeTo only for the floating-point value total_revenue while keeping exact matches for other fields. This would provide more precise validation for non-numeric fields. integ-test/src/test/java/org/opensearch/sql/calcite/tpch/CalcitePPLTpchIT.java [317] -closeTo(10, "Supplier#000000010", "Saygah3gYWMp72i PY", "34-852-489-8585", 797313.3838) +rows(10, "Supplier#000000010", "Saygah3gYWMp72i PY", "34-852-489-8585", closeTo(797313.3838, 0.01)) Suggestion importance[1-10]: 8 __ Why: The suggestion correctly identifies that closeTo is being applied to all parameters including non-numeric fields, when it should only be used for the floating-point total_revenue value. This is a significant correctness issue that could lead to improper test validation.	Medium