chore(chart-deps): update istio to version 1.28.3

[svcAPLBot]

This PR updates the dependency base to version 1.28.3.

[svcAPLBot]

Comparison of Helm chart templating output:

@@ data.merged-values @@
! ± value change in multiline text (one insert, one deletion)
  {
    "affinity": {},
    "autoscaleBehavior": {},
    "autoscaleEnabled": true,

  [124 lines unchanged)]

      },
      "sts": {
        "servicePort": 0
      },
-     "tag": "1.28.2",
+     "tag": "1.28.3",
      "variant": "",
      "waypoint": {
        "affinity": {},
        "nodeSelector": {},

  [119 lines unchanged)]

    "variant": "",
    "volumeMounts": [],
    "volumes": []
  }



@@ spec.template.spec.containers.discovery.image @@
! ± value change
- docker.io/istio/pilot:1.28.2
+ docker.io/istio/pilot:1.28.3


@@ data.values @@
! ± value change in multiline text (one insert, one deletion)
  {
    "gateways": {
      "seccompProfile": {},
      "securityContext": {}

  [99 lines unchanged)]

      },
      "sts": {
        "servicePort": 0
      },
-     "tag": "1.28.2",
+     "tag": "1.28.3",
      "variant": "",
      "waypoint": {
        "affinity": {},
        "nodeSelector": {},

  [29 lines unchanged)]

      "rewriteAppHTTPProbe": true,
      "templates": {}
    }
  }










@@ data.core.yaml @@
! ± value change in multiline text (one insert, one deletion)
  adminApps:
  - deps:
    - prometheus
    ingress:

  [412 lines unchanged)]

      about: Istio is an open platform for providing a uniform way to integrate microservices,
        manage traffic flow across microservices, enforce policies and aggregate telemetry
        data. Istio's control plane provides an abstraction layer over the underlying
        cluster management platform.
-     appVersion: 1.28.2
+     appVersion: 1.28.3
      integration: App Platform has security best practices built in, and is designed
        for intrusion. Istio is used by App Platform as a service mesh to deliver mTLS
        enforcement for all traffic that is deemed compromisable, egress control to
        force teams to choose explicit egress endpoints, and advanced routing capabilities

  [371 lines unchanged)]

      svc: tekton-dashboard
      type: public
    name: tekton
    ownHost: true