Update grafana dashboards to ray 2.49.2 + add README instructions on how to update

[alanwguo]

Why are these changes needed?

There have been some steady improvements to the grafana dashboards, updating kube-ray's static dashboard configs to have the latest version.

Also adds instructions for the process of updating for future devs.

Related issue number

Checks

• I've made sure the tests are passing.
• Testing Strategy
  • Unit tests
  • Manual tests
  • This PR is not tested :(

[win5923]

Thanks @alanwguo! I think we can wait to merge until the default Ray version is upgraded to 2.49.2 in Kuberay.

Maybe in 1.5.0

[alanwguo]

Thanks @alanwguo! I think we can wait to merge until the default Ray version is upgraded to 2.49.2 in Kuberay.

Maybe in 1.5.0

thanks, sounds good. Is there a place I can track the status of that? Or will someone merge this for me automatically once that's done?

First time contributing to kube-ray.

[win5923]

thanks, sounds good. Is there a place I can track the status of that? Or will someone merge this for me automatically once that's done?

Yes, I’ll ping @Future-Outlier to help with this once we upgrade the default Ray version to 2.49.2.