Updated documentation of remove subscriber in publish-subscribe model

Author: ronodhirSoumik

publish-subscribe/src/main/java/com/iluwatar/publish/subscribe/model/Topic.java

@@ -51,7 +51,7 @@ public void addSubscriber(Subscriber subscriber) {
   }
 
   /**
-   * Remove a subscriber to the list of subscribers.
+   * Remove a subscriber from the list of subscribers.
    *
    * @param subscriber subscriber to remove
    */