Implement best practices for k8s-dns-node-cache-app app

[LolloneS]

Coming from here.

The goal of this issue is to have the App eventually adhere to standard cloud-native best-practices. The points below are to be considered non-exhaustive. Feel free to add some that make sense and remove some that don't. If this issue does not make sense (e.g. is a duplicate or covers a deprecated app) please close it.

Expected outcome:

• the app has properly set PDBs (as percentages)
• the app can scale horizontally based on Custom Metrics (if it makes sense)
• the app runs with more than 1 replica by default (if it needs HA)
• the app does not use emptyDir volumes if not strictly necessary

[JosephSalisbury]

and @T-Kukawka also here hihihi <3

[mcharriere]

This app is actually own by Cabbage.

About the requirement, none of the points make sense. The app runs a daemonset; so no scaling, PDB or HA.
It has an emptyDir; which is needed.

If it's ok with you; let's close it.

[T-Kukawka]

moved to cabbage ✔️

[weatherhog]

fine for me to close