test: add new prometheus integration without kafak

[jetjinser]

Prometheus --vector--> RisingWave --Postgres data source--> Grafana

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What's changed and what's your intention?

Prometheus --vector--> RisingWave --Postgres data source--> Grafana

Prometheus is used as short-term storage, without kafka as middleware.
Data is inserted into RisingWave through Vector, and Grafana directly uses RisingWave as the data source.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added test labels as necessary. See details.
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

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Release note

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[github-actions]

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