Cost monitoring backend can be installed as a standalone helm-chart repository (phase 2)

[agoose77]

Context

This issue tracks the follow-up work to complete #6391.

See #6391 for the context:

The current cost reporting implementation is incorporated as part of the 2i2c infrastructure repository through mounted files in the aws-ce-grafana-backend helm chart. We should separate this into its own standalone repository so that other users can independently install the cost reporting tool using helm in line with our right to replicate policy.

Definition of Done

• Code review
  • [cost monitoring] Configure and roll out cost-monitoring across AWS clusters #6515
• Deploy across all AWS hubs
  • [docs] JupyterHub Cost Monitoring #6488

[yuvipanda]

@jnywong can you add in an estimate?

[jnywong]

I've added a 3 estimate. I would like another review @yuvipanda on #6515 by the end of the week, so that I can take a little a time at the weekend to terraform apply changes to minimise disruption.

[jnywong]

I've made requested changes and feel a bit bolder and can terraform apply any changes in my UK morning !