allow safely define http and https proxy with credentials

[rubroboletus]

Is your feature request related to a problem?/Why is this needed
In helm chart, we need to define a http and https proxy with credentials for efs-csi-controller in a safe way.

/feature

Describe the solution you'd like in detail
Our proxy servers need authentication and we do not like to expose credentials inside deployment definition using controller.env variables. Better is to use secret and fill this variables from secret in deployment.

Describe alternatives you've considered
There really isn't a safe alternative.

Additional context
N/A