Fix weird behavior of TS3Api#setMessageReadFlag

Author: rogermb

src/main/java/com/github/theholywaffle/teamspeak3/TS3Api.java

@@ -3461,10 +3461,7 @@ public boolean setMessageRead(Message message) {
 	 */
 	public boolean setMessageReadFlag(int messageId, boolean read) {
 		final CMessageUpdateFlag flag = new CMessageUpdateFlag(messageId, read);
-		if (query.doCommand(flag)) {
-			return flag.getError().isSuccessful();
-		}
-		return read;
+		return query.doCommand(flag);
 	}
 
 	/**