[5.x] Update SECURITY.md (#11996)

Author: duncanmcclean

SECURITY.md

@@ -3,7 +3,7 @@ If you discover a security vulnerability in Statamic, please review the followin
 ## Guidelines
 While working to identify potential security vulnerabilities in Statamic, we ask that you:
 
-- **Privately** share any issues that you discover with us via statamic.com/support as soon as possible.
+- **Privately** share any issues that you discover with us via support@statamic.com as soon as possible.
 - Give us a reasonable amount of time to address any reported issues before publicizing them.
 - Only report issues that are in scope.
 - Provide a quality report with precise explanations and concrete attack scenarios.