Add PodDisruptionBudgets for all KCP components

[cbuto]

This PR adds an optional PodDisruptionBudget for KCP, front proxy, and etcd. This ensures that each component remains available during node draining/upgrades.

KCP server - if enabled, defaults to minAvailable = 1 front proxy - same as KCP server. if enabled, defaults to minAvailable = 1 etcd - if enabled, defaults to maxUnavailable = 1

Tested locally via updating the ./hack/kind-values.yaml

diff --git a/hack/kind-values.yaml b/hack/kind-values.yaml
index b14c13f..0b8358c 100644
--- a/hack/kind-values.yaml
+++ b/hack/kind-values.yaml
@@ -1,14 +1,22 @@
 externalHostname: "kcp.dev.local"
 etcd:
-  enabled: false
+  enabled: true
+  podDisruptionBudget:
+    enabled: true
 kcp:
+  replicas: 2
   # tag is set via --set flag to make it more dynamic for testing purposes
   volumeClassName: "standard"
   tokenAuth:
     enabled: true
   etcd:
-    serverAddress: embedded
+    serverAddress: ""
+  podDisruptionBudget:
+    enabled: true
 kcpFrontProxy:
+  replicas: 2
+  podDisruptionBudget:
+    enabled: true
   # tag is set via --set flag to make it more dynamic for testing purposes
   openshiftRoute:
     enabled: false

k get poddisruptionbudgets -A

NAMESPACE   NAME              MIN AVAILABLE   MAX UNAVAILABLE   ALLOWED DISRUPTIONS   AGE
kcp         kcp               1               N/A               1                     6m44s
kcp         kcp-etcd          N/A             1                 1                     6m44s
kcp         kcp-front-proxy   1               N/A               1                     6m44s

[kcp-ci-bot]

Hi @cbuto. Thanks for your PR.

I'm waiting for a kcp-dev member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[sttts]

/ok-to-test

[mjudeikis]

/lgtm /Approve

[kcp-ci-bot]

LGTM label has been added.

Git tree hash: dee2f18489e9308d9fa5d012987b653138a3dc50

[kcp-ci-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mjudeikis

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