Add namespace to pipeline pause metrics

[chandankumar4]

Summary

What change needs making?

• Add pipeline namespace field for pipeline pause metrics

Ex: Current metrics

numaflow_pipeline_paused_seconds{intuit_alert="true",name="msaas-air-event-processor"} 403656.929848553

Use Cases

When would you use this?

• This will help user to figure out the pipeline is running in which namespace via metrics dashboard

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Message from the maintainers:

If you wish to see this enhancement implemented please add a 👍 reaction to this issue! We often sort issues this way to know what to prioritize.