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

[arkodg]

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.

[arkodg]

cc @qicz