## What changes were proposed in this pull request?
The second arg in method `update()` is never used. So I delete it.

## How was this patch tested?
local run with `./bin/spark-submit examples/src/main/python/als.py`

Author: Zheng RuiFeng <ruifengz@foxmail.com>

Closes #14247 from zhengruifeng/als_refine.