Add ability to create an issue from a standalone vulnerability

• Related issue: #196767 (closed)
• Depends on: !22823 (merged)

What does this MR do?

This adds a Create issue button in the standalone vulnerability page. Clicking on this button triggers an AJAX request to create an issue in the background. When the request resolves, the user is redirected to the new issue.

create_issue

NOTE: It's currently possible to create multiple issues from the same standalone vulnerability page. In a future iteration, we'll most likely want to hide the button if an issue already exists.

Screenshots

Before	After

How to test this?

1. Make sure you have enabled the first_class_vulnerabilities feature flag
2. Make sure you have a project with security scans enabled that has some vulnerabilities
3. Navigate to one of the vulnerabilities' standalone page from Security & Compliance > Vulnerability List
4. Click on the Create issue button

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