Fix the issue of unexpected results generated by groupBy queries when containing subqueries.#17598

[soullkk]

Fixes the issue of unexpected results generated by groupBy queries when containing subqueries#17598 .

Description

When processing groupby subqueries, it is necessary to finalize the returned results by the subqueries to support the aggregation operation of results by outer queries.

Fixed the bug that unexpected results generated by groupBy queries when containing subqueries.

When the groupBy subquery uses the longLast aggregator, the returned result is similar to Pair{lfs=xxx, lrs=xxx}, and it needs to be fanalized to support longSum or other aggregation operations in the outer groupBy query.

Before executing the outer aggregator, like longSum, the results of the subquery need to be transformed as follows:

• Pair{lfs=xxx, lrs=###} -> ###

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Key changed/added classes in this PR

• GroupByQueryQueryToolChest.java

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This PR has:

• been self-reviewed.
  • using the concurrency checklist (Remove this item if the PR doesn't have any relation to concurrency.)
• added documentation for new or modified features or behaviors.
• a release note entry in the PR description.
• added Javadocs for most classes and all non-trivial methods. Linked related entities via Javadoc links.
• added or updated version, license, or notice information in licenses.yaml
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage is met.
• added integration tests.
• been tested in a test Druid cluster.