Add new metrics for prometheus emitter

[ztzxt]

Description

I have updated https://github.com/apache/druid/blob/master/extensions-contrib/prometheus-emitter/src/main/resources/defaultMetrics.json and added the query/timeout/count, mergeBuffer/pendingRequests, ingest/events/processedWithError, ingest/notices/queueSize and segment/count metrics.

I also changed the description for query/interrupted/count according to https://druid.apache.org/docs/latest/operations/metrics/

Release note

Improved: Add some missing metrics to the default prometheus-emitter mapping

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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.