Add SECURITY.md with security reporting guidelines

Author: yoshiko-pg

SECURITY.md

@@ -0,0 +1,12 @@
+# Security Policy
+
+## Reporting Security Issues
+
+Please do not report security vulnerabilities through public GitHub issues.
+
+Instead, please report them to the Security Team.
+
+```
+Knowledge Work Security Team
+[email protected]
+```