[SPARK-24102][ML][MLLIB][PYSPARK][FOLLOWUP] Added weight column to pyspark API for regression evaluator and metrics

[imatiach-msft]

What changes were proposed in this pull request?

Followup to PR #17085
This PR adds the weight column to the pyspark side, which was already added to the scala API.
The PR also undoes a name change in the scala side corresponding to a change in another similar PR as noted here:
#17084 (comment)

How was this patch tested?

This patch adds python tests for the changes to the pyspark API.

Please review http://spark.apache.org/contributing.html before opening a pull request.

[SparkQA]

Test build #103885 has finished for PR 24197 at commit b26b0f5.

• This patch fails Scala style tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class RegressionEvaluator(JavaEvaluator, HasLabelCol, HasPredictionCol, HasWeightCol,

[SparkQA]

Test build #103886 has finished for PR 24197 at commit 494e8aa.

• This patch fails to build.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class RegressionEvaluator(JavaEvaluator, HasLabelCol, HasPredictionCol, HasWeightCol,

[srowen]

OK, yeah seems consistent given the other PRs

[SparkQA]

Test build #103891 has finished for PR 24197 at commit d050f32.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class RegressionEvaluator(JavaEvaluator, HasLabelCol, HasPredictionCol, HasWeightCol,

[SparkQA]

Test build #103893 has finished for PR 24197 at commit f659fb2.

• This patch fails due to an unknown error code, -9.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class RegressionEvaluator(JavaEvaluator, HasLabelCol, HasPredictionCol, HasWeightCol,

[HyukjinKwon]

retest this please

[SparkQA]

Test build #103898 has finished for PR 24197 at commit f659fb2.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class RegressionEvaluator(JavaEvaluator, HasLabelCol, HasPredictionCol, HasWeightCol,

[SparkQA]

Test build #103939 has finished for PR 24197 at commit 4cb2137.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class RegressionEvaluator(JavaEvaluator, HasLabelCol, HasPredictionCol, HasWeightCol,

[imatiach-msft]

retest this please

[SparkQA]

Test build #103945 has finished for PR 24197 at commit 4cb2137.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class RegressionEvaluator(JavaEvaluator, HasLabelCol, HasPredictionCol, HasWeightCol,

[srowen]

Merged to master