apollo-common/src/main/java/com/ctrip/framework/apollo/common/http/RichResponseEntity.java/RichResponseEntity/ok
class RichResponseEntity:  public static <T> RichResponseEntity<T> ok(T body){
    RichResponseEntity<T> richResponseEntity = new RichResponseEntity<>();
    richResponseEntity.message = HttpStatus.OK.getReasonPhrase();
    richResponseEntity.code = HttpStatus.OK.value();
    richResponseEntity.body = body;
    return richResponseEntity;
  }