Sync release notes of iRedMail Easy.

en_US/iredmail-easy/4-iredmail-easy.release.notes.md

@@ -22,6 +22,8 @@
     - Log slow process if doesn't finish in 20 seconds.
 
 * Fixed issues:
+    - Security vulnerability: It generates same random passwords for different
+      hosts in some cases.
     - Minor issue while setting up MariaDB on CentOS 8.
 
 * Package updates:

html/iredmail-easy.release.notes.html

@@ -87,6 +87,8 @@
 <li>
 <p>Fixed issues:</p>
 <ul>
+<li>Security vulnerability: It generates same random passwords for different
+  hosts in some cases.</li>
 <li>Minor issue while setting up MariaDB on CentOS 8.</li>
 </ul>
 </li>