Fix kubernetes provider documentation

[tetianakravchenko]

• fix namespace fields
• add information about the deployment and cronjob settings in add_resource_metadata

[github-actions]

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[mergify]

This pull request does not have a backport label. Could you fix it @tetianakravchenko? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-/d./d is the label to automatically backport to the /d./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[kilfoyle]

LGTM!

[tetianakravchenko]

@kilfoyle seems I don't have an option to merge it in, could you please help with it?