Memoize the redundant calls to overlord in sql statements endpoint

[Akshat-Jain]

Description

With the changes in #16808, we are contacting overlord multiple times for fetching task reports which is redundant, and may cause performance issues.

This PR changes the implementation to memoize the fetched response and remove redundant calls to overlord.

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This PR has:

• been self-reviewed.
• 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.