Sidecar containers images configurable at runtime

[doodlesbykumbi]

Is your feature request related to a problem? Please describe.

At present the sidecar injector relies on configuration of the sidecar container images at deploy time. This means if you want to upgrade/change sidecar container images you have to redeploy. This would incur downtime for such a critical component.

Describe the solution you would like

Runtime configuration avoids the problem altogether. It allows the application to seamlessly change the container images at runtime.

Describe alternatives you have considered

N/A

Additional context

N/A