fix(core): auto add ops metrcis

[woshigaopp]

This pull request refactors the logic for generating metrics exporter URIs in AutoMQConfig.java, focusing on improving clarity and correctness in handling legacy and new configuration options. The main changes include renaming methods and code identifiers for consistency, updating how OPS exporter URIs are constructed, and removing unnecessary imports.

Refactoring and logic improvements:

• Updated the genMetricsExporterURI method to check for a null URI and fall back to legacy config construction, and ensured OPS exporter URIs are always included if missing.
• Renamed legacy metrics exporter URI methods and related code identifiers from S3Exporter to OpsExporter for clarity and consistency. [1] [2] [3]

Legacy exporter logic cleanup:

• Removed the case for TELEMETRY_EXPORTER_TYPE_OPS in legacy config processing, ensuring OPS exporter URIs are only added via the updated logic.
• Simplified the joining of exporter URIs by removing the use of streams and collectors, replacing it with a direct String.join.

Codebase maintenance:

• Removed an unused import of java.util.stream.Collectors from the top of the file.More detailed description of your change,
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Summary of testing strategy (including rationale)
for the feature or bug fix. Unit and/or integration
tests are expected for any behaviour change and
system tests should be considered for larger changes.

Committer Checklist (excluded from commit message)

• Verify design and implementation
• Verify test coverage and CI build status
• Verify documentation (including upgrade notes)