Security Management: WF: Create/Maintain Security Plan

The workflow https://eclipse-score.github.io/process_description/main/process_areas/security_management/security_management_workflow.html
shall be checked and completed according the general guidance in the parent EPIC.

- [x] Is the description of the workflow complete, correct?
- [x] Is the getting started linked, and the workflow properly contained in the getting started document?
- [x] Is the concept linked, and the workflow properly contained in the concept document?
- [x] Is the guidance complete, correct, consistent? (Guideline, Method, Checklist, Template)
- [x] Are all linked guidance identified correct, consistent?
- [x] Are all linked templates copied properly in the Template Folder?
- [x] Are all roles properly defined (Responsible, Approver, Supporter)?
- [x] Is the project specific Role, Security Manager description reflecting the workflow under responsibilities?
- [x] Are process requirements defined, if applicable and showing-up under satisfied?