Incorrect Method Call in getLabels

[emeth-kim]

There is a minor bug in the getLabels method.

https://github.com/vinhkhuc/JFastText/blob/130e5e0243e8946124ba8bfa7ab81175bb1995b7/src/main/java/com/github/jfasttext/JFastText.java#L108-L110

should be

public List<String> getLabels() { 
    return stringVec2Strings(fta.getLabels()); 
}