247: Add namespace metadata option in templates r=brunoocasali a=MannerManThis sets the namespace key in metadata for all kubernetes manifests. The `.Release.Namespace` is a built-in variable in helm, that can be passed with `--namespace` on `install` or `template` step. If not set it defaults to `default`.**Why?**When using `helm install` with the `--namespace` argument the templates are applied into the chosen namespace.When using helm only as a template engine, in combination with GitOps tools like Flux, the namespace property must be set in the rendered manifests to be applied. For `--namespace` to have an effect when using `helm template`, it must be present like this in the templates.This change should not have any effect/change for `helm install` approach as far as I know.# Pull Request## Related issuePossibly a fix for#230## What does this PR do?- Sets the namespace key in metadata for all kubernetes manifests## PR checklistPlease check if your PR fulfills the following requirements:- [ x ] Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?- [ x ] Have you read the contributing guidelines?- [ x ] Have you made sure that the title is accurate and descriptive of the changes?Co-authored-by: Oscar <oscar@eth1.nu>Co-authored-by: Bruno Casali <brunoocasali@gmail.com>Co-authored-by: brunoocasali <brunoocasali@users.noreply.github.com>