Add detected note to vulnerability details page

What does this MR do?

When viewing a single vulnerability on the security dashboard, the vulnerability's state will be shown in the header:

When the state is Detected, the detection time and the pipeline will be shown. If the state is changed, it will instead show which user and when they changed the state:

However, we lose information on which pipeline failed and when. This MR adds that info to the bottom of the page as a system note:

This note is always shown, even if the current vulnerability state is Detected. This implements the design from this issue: #222346 (closed)

Design

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done