Update security reporting instructions in SECURITY.md

Removed direct contact for Wicket PMC from security reporting.

SECURITY.md

diff --git a/SECURITY.md b/SECURITY.md
index 1a152a6..ecd48f9 100644
--- a/SECURITY.md
+++ b/SECURITY.md
@@ -11,8 +11,7 @@
 Report suspected vulnerabilities privately to:
 
 - **security@apache.org** — the ASF Security Team, who will forward the report
-  to the Wicket PMC, or
-- **private@wicket.apache.org** — the Wicket PMC directly.
+  to the Wicket PMC.
 
 A useful report includes: