Update README.md (#748)

Fixed an example of AtlasProject

Author: igor-karpukhin

README.md

@@ -52,7 +52,7 @@ spec:
   projectIpAccessList:
     - ipAddress: "192.0.2.15"
       comment: "IP address for Application Server A"
-    - ipAddress: "203.0.113.0/24"
+    - cidrBlock: "203.0.113.0/24"
       comment: "CIDR block for Application Server B - D"
 EOF
 ```