feat: Support pod priorityClassName

[jsirianni]

Description of Changes

• Added priorityClassName for all all deployments
• Updated some docs for unrelated parameters

You can do this in your values file:

Please check that the PR fulfills these requirements

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• CI passes
• Changes to ports, services, or other networking have been tested with istio

I deployed BindPlane HA w/ NATs.

I created a priority class:

apiVersion: scheduling.k8s.io/v1
kind: PriorityClass
metadata:
  name: high-priority
value: 1000000
globalDefault: false

And then I updated my values to include this:

priorityClassName:
  bindplane: "high-priority"
  nats: "high-priority"
  jobs: "high-priority"
  prometheus: "high-priority"
  transform_agent: "high-priority"

When I get pod -o yaml, I see:

    priorityClassName: high-priority
    priorityClassName: high-priority
    priorityClassName: high-priority
    priorityClassName: high-priority
    priorityClassName: high-priority
    priorityClassName: high-priority
    priorityClassName: high-priority