Docs: Improve examples on overriding deployment resources

[oraNod]

Follows up on #20 (comment)

Purpose is to improve documentation in README at

awx-operator-helm/README.md

Line 249 in 70bac70

### Controller

While the example of the replica is valid. This is not really a common scenario to customize the operator replica (maybe to scale up/scale down). One more common use case is to specify a different container image for each container as seen in #17 or #27 to cover disconnected/restricted environments.
Another useful example would be to provide an example for setting up resource requests and limits, this would cover #14.

[miles-w-3]

Adding additional context from the other thread as well, This is more of a feature because the naive override approach would have to be overriding the entire container list since helm does not support merging lists together.

The alternative is to improve the templating logic to offer a containerConfigOverride key or something similar where you can provide a key which matches a container name and the values you want to layer in, and then helm template logic to loop through the containers list from the original operator and splice the override configs in. This is something I can work on once we get releases going

#20 (comment)

[miles-w-3]

Will be closed in #48