[ENH] - Scheduled Nebari Backups

[pt247]

Feature description

We want to expand the existing configuration to allow it to specify backup parameters. Backing up Nebari includes the following:

1. KeyCloak user details.
2. User data
3. Conda environments

Interface

backup
  location: <BACKUP LOCATION>>
  schedule: <CRON EXPRESSION>
  retention_period: <NUMBER OF DAYS>

Implementation

There are several ways this can be achieved:

1. Kubernetes CronJob
   1. Pros:
      1. Native to K8
      2. Good for simple disconnected tasks
   2. Cons: 2. Will need to custom build and maintain status, monitoring, and alerting.
2. Argo Workflows
   1. Pros:
      1. Fully featured UI
      2. Native artifact support
      3. Workflow archive
      4. Rest API
   2. Cons:
      1. Argo becomes a core component in Nebari.
      2. Most of our workflows might not be DAGs; it's possible that all the tasks can be independently executed.

Value and/or benefit

1. It will save the state from accidental deletes.

Anything else?

No response

### Tasks
- [x] Add the pros and cons of each of the available options.
- [ ] Discuss available options

[Adam-D-Lewis]

BTW, I think you would use k8s Jobs instead of k8S Cronjobs. Also, one option to run things sequentially with k8s Jobs - https://stackoverflow.com/questions/40713573/how-to-run-containers-sequentially-as-a-kubernetes-job (haven't tried it myself, but worth a try)

[pt247]

Closing in favor of #2518