[SPARK-29269][PYTHON][ML] Pyspark ALSModel support getters/setters

### What changes were proposed in this pull request?
Add getters/setters in Pyspark ALSModel.

### Why are the changes needed?
To keep parity between python and scala.

### Does this PR introduce any user-facing change?
Yes.
add the following getters/setters to ALSModel
```
get/setUserCol
get/setItemCol
get/setColdStartStrategy
get/setPredictionCol
```

### How was this patch tested?
add doctest

Closes #25947 from huaxingao/spark-29269.

Authored-by: Huaxin Gao <huaxing@us.ibm.com>
Signed-off-by: zhengruifeng <ruifengz@foxmail.com>

mllib/src/main/scala/org/apache/spark/ml/recommendation/ALS.scala

@@ -131,7 +131,7 @@ private[recommendation] trait ALSModelParams extends Params with HasPredictionCo
  * Common params for ALS.
  */
 private[recommendation] trait ALSParams extends ALSModelParams with HasMaxIter with HasRegParam
-  with HasPredictionCol with HasCheckpointInterval with HasSeed {
+  with HasCheckpointInterval with HasSeed {
 
   /**
    * Param for rank of the matrix factorization (positive).