EXP figure out way to only schedule IDEs on nodes where a longhorn-manager is running

[wabscale]

We may need to create some kind of a poller / cronjob that updates node labels when longhorn is ready.

Potential options for implementation:

• Node Affinities
• Node Labels

[wabscale]

https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/

https://longhorn.io/

[wabscale]

We're going to need to start with a simple python job (like https://github.com/AnubisLMS/Anubis/blob/master/api/jobs/poller.py for example) that lists the pods on each node, then adds a label to the nodes that have a longhorn-manager pod running. We're pretty much just going to need to need to figure out which of the functions in this huge markdown file https://github.com/kubernetes-client/python/blob/master/kubernetes/README.md are the right functions to call to list pods on a node, then update node labels.