feat: allow namespace overrides

[fernandezcuesta]

Add the ability to control the destination namespace for each chart, useful when deploying under umbrella charts.

Fix: #3798

[nikola-jokic]

Can you please add tests?

[fernandezcuesta]

@nikola-jokic done

[nikola-jokic]

Hey @fernandezcuesta,

Can you also resolve conflicts. Sorry, I can do it for you if you want.

[nikola-jokic]

Suggested few updates for clarity.
You need to add import for these:

import metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

[nikola-jokic]

LGTM Thanks!