[stable/k8s-resources]: introduce enabled flag

[eshepelyuk]

Description

In case when values.yaml is not static, but generated, using tools like helmfile, or KCL or any other. It's often needed to dynamically enable / disable some resources based on certain conditions. For example using Helm like syntax

values.gotmpl.yaml

{{- $condition1 := .... -}}
{{- $condition2 := .... -}}
ServiceAccounts:
  {{- if $condition1 }}
  - fullnameOverride: sa1
    annotations: 
      foo: bar1
  {{- end }}
  {{- if $condition2 }}
  - fullnameOverride: sa2
    annotations: 
      foo: bar2
  {{- end }}
  {{- if or $condition1 $condition2 }}
  - fullnameOverride: sa3
    annotations: 
      foo: bar3
  {{- end }
  - fullnameOverride: sa4
    annotations: 
      foo: bar4

With this PR the above fragment could be rewritten like below, resulting in more readable and concise code.

values.gotmpl.yaml

{{- $condition1 := .... -}}
{{- $condition2 := .... -}}
ServiceAccounts:
  - fullnameOverride: sa1
    enabled: {{- $condition1 -}}
    annotations: 
      foo: bar1
  - fullnameOverride: sa2
    enabled: {{- $condition2 -}}
    annotations: 
      foo: bar2
  - fullnameOverride: sa3
    enabled: {{- or $condition1 $condition2 -}}
    annotations: 
      foo: bar3
  - fullnameOverride: sa4
    annotations: 
      foo: bar4

Checklist

• Title of the PR starts with chart name (e.g. [stable/mychartname])
• I have read the contribution instructions, bumped chart version and regenerated the docs
• Github actions are passing

[max-rocket-internet]

Maybe some explanation as to why this is needed?

[eshepelyuk]

Maybe some explanation as to why this is needed?

Added description to a PR as requested.

[max-rocket-internet]

Thanks for the explanation @eshepelyuk, looks good!