hardcode kustomize download to bypass github api rate limits

Signed-off-by: Triona Doyle <tekton@example.com>

Author: Triona Doyle

openshift-ci/build-root/Dockerfile

@@ -4,6 +4,7 @@ FROM quay.io/devtools_gitops/go-toolset:1.26.2
 USER root
 
 ARG OPERATOR_SDK_VERSION=1.35.0
+ARG KUSTOMIZE_VERSION=v5.8.1
 
 # Install kubectl tool which is used in e2e-tests
 RUN curl -sSL -o /usr/local/bin/kubectl "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl" && \
@@ -14,8 +15,7 @@ RUN curl -sSL -o /usr/local/bin/argocd https://github.com/argoproj/argo-cd/relea
      chmod +x /usr/local/bin/argocd
 
 # Install Kustomize
-RUN wget https://raw.githubusercontent.com/kubernetes-sigs/kustomize/master/hack/install_kustomize.sh && \
-    bash install_kustomize.sh /usr/local/bin && rm install_kustomize.sh
+RUN curl -sSL https://github.com/kubernetes-sigs/kustomize/releases/download/kustomize%2F${KUSTOMIZE_VERSION}/kustomize_${KUSTOMIZE_VERSION}_linux_amd64.tar.gz | tar -xz -C /usr/local/bin
 
 # Install operator-sdk
 RUN curl -L -o /usr/local/bin/operator-sdk https://github.com/operator-framework/operator-sdk/releases/download/v${OPERATOR_SDK_VERSION}/operator-sdk_linux_amd64 && \