apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/entity/Commit.java/Commit/toString
class Commit:  @Override
  public String toString() {
    return toStringHelper().add("changeSets", changeSets).add("appId", appId).add("clusterName", clusterName)
        .add("namespaceName", namespaceName).add("comment", comment).toString();
  }