Fix kustomize 5 warning for /common/knative/knative-serving/overlays/gateways

[annajung]

Part of #2388 to support kustomize 5 without warnings. Fix the use of deprecated fields in manifests/common/knative/knative-serving/overlays/gateways

Steps To Reproduce

1. Download kustomize 5.0.0

2. Run kustomize build using version kustomize 5.0.0 to see the warning

git clone https://github.com/kubeflow/manifests.git
cd manifests/common/knative/knative-serving/overlays/gateways
kustomize build . > tmp.yaml

Current Behavior

Step 2 produces the following warning

# Warning: 'patchesStrategicMerge' is deprecated. Please use 'patches' instead. Run 'kustomize edit fix' to update your Kustomization automatically.
# Warning: 'patchesStrategicMerge' is deprecated. Please use 'patches' instead. Run 'kustomize edit fix' to update your Kustomization automatically.

Expected Behavior

Step 2 completes without a warning and produces the same yaml as before the changes

Helpful links:

• https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/replacements/
• https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/resource/
• https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/patches/

Where does the fix belong?

/common directory is managed by the Manifest WG, PR should be made to the manifests repo

/help
/good-first-issue

[google-oss-prow]

@annajung:
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In response to this:

Part of #2388 to support kustomize 5 without warnings. Fix the use of deprecated fields in manifests/common/knative/knative-serving/overlays/gateways

Steps To Reproduce

1. Download kustomize 5.0.0

2. Run kustomize build using version kustomize 5.0.0 to see the warning

git clone https://github.com/kubeflow/manifests.git
cd manifests/common/knative/knative-serving/overlays/gateways
kustomize build . > tmp.yaml

Current Behavior

Step 2 produces the following warning

# Warning: 'patchesStrategicMerge' is deprecated. Please use 'patches' instead. Run 'kustomize edit fix' to update your Kustomization automatically.
# Warning: 'patchesStrategicMerge' is deprecated. Please use 'patches' instead. Run 'kustomize edit fix' to update your Kustomization automatically.

Expected Behavior

Step 2 completes without a warning and produces the same yaml as before the changes

Helpful links:

• https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/replacements/
• https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/resource/
• https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/patches/

Where does the fix belong?

/common directory is managed by the Manifest WG, PR should be made to the manifests repo

/help
/good-first-issue

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[juliusvonkohout]

@annajung Fixed by #2515, please merge

[juliusvonkohout]

/assign @juliusvonkohout