fix(knative): update PDBs to allow node drain

[aniketpati1121]

✏️ Summary of Changes

• Updated PodDisruptionBudgets (PDBs) for Knative core components (activator, webhook, eventing-webhook)
• Adjusted minAvailable and replicas to allow safe node drain for single-replica deployments
• Ensures cluster maintenance can proceed without manually evicting pods or blocking drains

🐛 Related Issues

Fixes #3313

[google-oss-prow]

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[juliusvonkohout]

Hello, please make sure that you are on the latest master branch with the Knative 1.20 commit. please rebase your branch if not and never merge from master

[aniketpati1121]

Hello, please make sure that you are on the latest master branch with the Knative 1.20 commit. please rebase your branch if not and never merge from master

Rebased onto latest master (Knative 1.20) — PR is now up-to-date and ready for review.

[aniketpati1121]

@juliusvonkohout @kimwnasptd I’ve updated the changes. Please review them

[juliusvonkohout]

/hold
Thank you for the PR. Please never ever change the upstream folder . It is managed by the synchronization scripts in /scripts. It is synchronized from Knative. You need to instead patch it in the overlays. For example here for knative-serving https://github.com/aniketpati1121/manifests/blob/fix-knative-pdb-single-replica/common/knative/knative-serving/base/kustomization.yaml and we need to see which patches we can drop. Maybe we can remove the seccompprofile patches for example.

[juliusvonkohout]

Maybe we can drop https://github.com/aniketpati1121/manifests/blob/fix-knative-pdb-single-replica/common/knative/knative-serving/base/patches/seccomp.yaml and https://github.com/aniketpati1121/manifests/blob/fix-knative-pdb-single-replica/common/knative/knative-serving/base/patches/sidecar-injection.yaml. in the end you can test it in this PR here. If all tests are green we are good.

[juliusvonkohout]

For knative-eventing https://github.com/aniketpati1121/manifests/blob/fix-knative-pdb-single-replica/common/knative/knative-eventing/base/kustomization.yaml

I am also on vacation so please expect delays.