## What changes were proposed in this pull request?
An RDD is created using LabeledPoint, but the comment is like #LabeledPoint(feature, label).
Although in the method ChiSquareTest.test, the second parameter is feature and the third parameter is label, it it better to write label in front of feature here because if an RDD is created using LabeldPoint, what we get are actually (label, feature) pairs.
Now it is changed as LabeledPoint(label, feature).
The comments in Scala and Java example have the same typos.
## How was this patch tested?
tested
https://issues.apache.org/jira/browse/SPARK-24688
Author: Weizhe Huang 492816239qq.com
Please review http://spark.apache.org/contributing.html before opening a pull request.
Closes#21665 from uzmijnlm/my_change.
Authored-by: Huangweizhe <huangweizhe@bbdservice.com>
Signed-off-by: Sean Owen <sean.owen@databricks.com>
6c66ab8b33