3scale Operator doesn't respect *_proxy env vars

The request is to enable the Operator pod to connect to an external 3scale environment through a proxy.

The use case is allowing the management of a separate 3scale environment's objects via CRDs defined in a cluster that requires a proxy to be able to connect to the target environment.

DEV NOTES: The PR linked makes the 3scale operator to respect HTTP(S)_PROXY environment variables
This is, however, a workaround, because it still requires to add those env vars to the operator container, and env vars should not be added/delete/updated for the operator by the customer.
For 2.12, we will be working on a explicit way to configure http proxies in the application capabilities CRDs