Use mgr.GetAPIReader() to read Secrets and ConfigMaps directly from the API Server

*Description*:
>Describe the desired behavior, what scenario it enables and how it
would be used.

Use the `GetAPIReader` handle instead of the `GetClient()` handle to read larger objects such as Secrets and ConfigMaps by not storing them in the Controller Runtime Cache and directly reading them from the API server

[optional *Relevant Links*:]
>Any extra documentation required to understand the issue.