Update Istio to 1.15.0

Package Merge Request

Package Changes

https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-controlplane/-/blob/1.15.0-bb.0/CHANGELOG.md

https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-operator/-/blob/1.15.0-bb.0/CHANGELOG.md

Package MR

https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-controlplane/-/merge_requests/125

https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-operator/-/merge_requests/58

For Issue

Closes https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-controlplane/-/issues/80

Closes https://repo1.dso.mil/platform-one/big-bang/apps/core/istio-operator/-/issues/35