Add actions section to vulnerability management policy editor_component

What does this MR do and why?

Related #465857 (closed)

Add actions section to vulnerability management policy editor_component

This adds the actions section to the editor component of the vulnerability management policy type. Currently, there is only 1 option, namely auto_resolve which renders as the label Resolved. When we work on auto-dismiss feature later on, this label will become a dropdown where you can select Resolved / Dismissed.

Because there's only 1 option at the moment, the default template already contains

actions:
  - type: auto_resolve

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Screenshots or screen recordings

invalid actions yaml

How to set up and validate locally

1. enable feature flag vulnerability_management_policy_type
2. go to a project
3. go to Secure > Policies
4. click New policy
5. click Select policy on the Vulnerability management policy card
6. validate it shows a yaml preview with

type: vulnerability_management_policy
name: ''
description: ''
enabled: true
actions:
  - type: auto_resolve

7. validate that if you change auto_resolve by something else or you remove the actions from the yaml, the actions section will still render but not display the "Resolved" label