feat(istio): Upgrade to 1.23.2 (#1511)

* feat(istio): Upgrade to 1.23.2

* fix(istio): Update chart.yaml patch

* fix(istio): Update dashboards copy logic

* chore: copy upstream chart 1.23.2

* chore: copy upstream chart grafana dashboards 1.23.2

* chore: apply patch_1_values.sh

* chore: apply patch_2_templates.sh

* chore: apply patch_3_chartyaml.sh

* chore: apply patch_4_deployment.sh

* fix(istio): Remove dashboard removed upstream

staging/istio/Chart.yaml

@@ -1,14 +1,13 @@
 apiVersion: v2
 name: istio
-version: 1.22.3
-appVersion: 1.22.3
+version: 1.23.2
+appVersion: 1.23.2
 description: Helm chart for deploying Istio operator
 keywords:
   - istio
   - operator
 sources:
   - https://github.com/istio/istio/tree/master/operator
-engine: gotpl
 icon: https://istio.io/latest/favicons/android-192x192.png
 maintainers:
   - name: goeldeepak