Update DOC_PATH_VULNERABILITY_REPORT to point to false_positive_detection docs

Problem

The DOC_PATH_VULNERABILITY_REPORT constant in the false positive detection banner was pointing to an incorrect documentation path. The banner's "Learn more" button should direct users to the false positive detection documentation, not the general vulnerability report index.

Solution

Updated the DOC_PATH_VULNERABILITY_REPORT constant to point to the correct documentation path for false positive detection.

Changes

• File: ee/app/assets/javascripts/security_dashboard/constants.js
• Changed from: user/application_security/vulnerability_report/_index
• Changed to: user/application_security/vulnerabilities/false_positive_detection

Impact

This affects the "Learn more" button in the false positive detection banner component (false_positive_detection_banner.vue), which will now correctly link to the false positive detection documentation.