removed duplicate CloudStack DRS feature from the list (#532)

Author: ingox

source/releasenotes/about.rst

@@ -62,7 +62,6 @@ new features. Some of the highlights include:
 • CloudStack DRS
 • OAuth2 Authentication
 • VNF Appliances Support
-• CloudStack DRS
 • CloudStack Snapshot Copy
 • Scheduled Instance Lifecycle Operations
 • Guest OS Management