Fix improper optional usage in velocity

velocity/src/main/java/co/aikar/commands/ACFVelocityUtil.java

@@ -61,7 +61,8 @@ public class ACFVelocityUtil {
         }
 
         Optional<Player> exactMatch = server.getPlayer(partialName);
-        if (exactMatch != null) {
+        //noinspection OptionalIsPresent
+        if (exactMatch.isPresent()) {
             return Collections.singleton(exactMatch.get());
         }