fix: update link to IRP Flowchart (#2116)

Co-authored-by: Ulises Gascón <ulisesgascongonzalez@gmail.com>

Author: skyeyeye

_posts/2025-06-05-vulnerability-reporting-process-overhaul.md

@@ -21,7 +21,7 @@ Thanks to support from the [Sovereign Tech Fund](https://sovereign.tech), the Ex
 
 A comprehensive runbook and process flow have been created to guide maintainers through each step of triaging, confirming, and addressing reported security issues.  
 - [View the documentation](https://github.com/expressjs/security-wg/blob/main/docs/incident_response_plan.md)  
-- [Security Report Handling Flowchart](https://github.com/expressjs/security-wg/blob/main/docs/handle_security_reports.md#security-report-handling-flowchart)
+- [Security Report Handling Flowchart](https://github.com/expressjs/security-wg/blob/main/docs/incident_response_plan.md#security-report-handling-flowchart)
 
 ### Unified Security Policy Across Repositories