chore(deps): update istio monorepo to v1.28.1

Author: renovate[bot]

infrastructure/istio/helmfile.d/05-istio-base.yaml

@@ -9,4 +9,4 @@ releases:
   - name: istio-base
     namespace: istio-system
     chart: istio/base
-    version: 1.15.0
+    version: 1.28.1

infrastructure/istio/helmfile.d/06-istio-cni.yaml

@@ -9,5 +9,5 @@ releases:
   - name: istio-cni
     namespace: kube-system
     chart: istio/cni
-    version: 1.15.0
+    version: 1.28.1
     installed: {{ eq .Environment.Name "cni" | toYaml }}

infrastructure/istio/helmfile.d/10-istiod.yaml

@@ -9,7 +9,7 @@ releases:
   - name: istiod
     namespace: istio-system
     chart: istio/istiod
-    version: 1.15.0
+    version: 1.28.1
     wait: true
     values:
       - ./values/istiod.values.yaml.gotmpl

infrastructure/istio/helmfile.d/11-istio-ingress.yaml

@@ -11,7 +11,7 @@ releases:
   - name: istio-ingressgateway
     namespace: istio-ingress
     chart: istio/gateway
-    version: 1.15.0
+    version: 1.28.1
     # this fails the installation because helm waits for the loadbalancer to get an ip.
     # But the IP is not available until someone runs minikube tunnel
     #wait: true