Add ChangeLog entry for #15621

Signed-off-by: William Desportes <williamdes@wdes.fr>

ChangeLog

@@ -9,6 +9,7 @@ phpMyAdmin - ChangeLog
 - issue        Fix php notice "Undefined index table_create_time" when setting displayed columns on results of a view
 - issue #15571 Fix fatal error when trying to edit row with row checked and button under the table
 - issue #15633 Fix designer set display field broken for php 5.x versions
+- issue #15621 Support CloudFront-Forwarded-Proto header for Amazon CloudFront proxy
 
 4.9.2 (2019-11-21)
 - issue #14184 Change the cookie name from phpMyAdmin to phpMyAdmin_https for HTTPS, fixes many "Failed to set session cookie" errors