[Feature][metrics] ray_job_submitter_pod_startup_duration_seconds

[troychiu]

Search before asking

• [x] I had searched in the issues and found no similar feature requirement.

Description

To enhance observability in KubeRay, we propose introducing a new metric: ray_job_execution_duration_seconds. This metric will measure the time from the creation of submitter pods to when they start running, providing valuable insights into submitter pod performance.

Metric Name	Type	Description	Labels
ray_job_submitter_pod_startup_duration_seconds	Histogram	The time between submitter pods created to running	- name (ray job’s name)

Are you willing to submit a PR?

• [x] Yes I am willing to submit a PR!

[troychiu]

cc @kevin85421 could you assign this to me? Thank you.