Istio injection for namespaces should be optional for all charts

Enable option to disable and enable istio injection for all charts

Description

The Istio injection is hardcoded as 'enabled' in this link: https://repo1.dso.mil/big-bang/bigbang/-/blob/master/chart/templates/loki/namespace.yaml#L10. I've noticed this inconsistency across multiple charts. The recent Istio upgrade has disrupted logging and monitoring. I've identified that Istio injection is the root cause, but currently, there's no way to disable it.

Provide any steps possible used to reproduce the error (ideally in an isolated fashion).

BigBang Version

Main/2.9.0

This can be retrieved multiple ways:

# Locations

https://repo1.dso.mil/big-bang/bigbang/-/blob/master/chart/templates/loki/namespace.yaml#L10
https://repo1.dso.mil/big-bang/bigbang/-/blob/2.9.0-rc.2/chart/templates/fluentbit/namespace.yaml#L10
I see many chart templates like this