feat: add pod disruption budgets

[sylr]

Reason for Change:

This allows the cluster-autoscaler to evict the pods of the concerned deployments.

Issue Fixed:

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes: Add pod disruption budgets

[codecov]

Codecov Report

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[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@208a8e0). Click here to learn what that means.
The diff coverage is n/a.

@@           Coverage Diff            @@
##             master    #218   +/-   ##
========================================
  Coverage          ?   53.2%           
========================================
  Files             ?      95           
  Lines             ?   14235           
  Branches          ?       0           
========================================
  Hits              ?    7574           
  Misses            ?    5995           
  Partials          ?     666

[jackfrancis]

@sylr Thanks for this! FYI I rebased/force pushed to enable our new E2E pipeline to run.

[jackfrancis]

This sort of seems like a no-op configuration, but I infer that cluster-autoscaler needs some value here in order to engage?

[sylr]

Absolutely. The cluster-autoscaler will refuse to engage in a node scale down if there are non-mirrored pods which do not have a PDB that allows the pod to be killed.

[jackfrancis]

/lgtm

[jackfrancis]

@mboersma, could you spend a small amount of time reading up on the PodDisruptionBudget spec and sanity check the functional intent here. LGTM but I'd like a 2nd opinion. :)

[mboersma]

/lgtm based on my reading of the cluster-autoscaler FAQ and the CA docs.

[acs-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jackfrancis, mboersma, sylr

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