Reflect user comment on vulnerability state change system note

When a user modifies the state (typically dismissal) of a vulnerability, they are able to add a comment. The current designs express desire to reflect this comment in the system note.

#267582[design_1682361393951.png]

Due caution will be necessary however, that we carefully check the contents of this field before presenting it, as we will need to check for and appropriately handle:

• Empty comment
• Overlong comment
• Attempted code injection (x-site scripting) or other tampering.
• Other possible bad behaviour.

Implementation Plan

• backend modify SystemNotes::VulnerabilitiesService#state_change_body in ee/app/services/system_notes/vulnerabilities_service.rb to include the user comment (if provided) in the system note generated.