[SPARK-28977][DOCS][SQL] Fix DataFrameReader.json docs to doc that partition column can be numeric, date or timestamp type

[srowen]

What changes were proposed in this pull request?

DataFrameReader.json() accepts a partition column that is of numeric, date or timestamp type, according to the implementation in JDBCRelation.scala. Update the scaladoc accordingly, to match the documentation in sql-data-sources-jdbc.md too.

Why are the changes needed?

scaladoc is incorrect.

Does this PR introduce any user-facing change?

No.

How was this patch tested?

N/A

[HyukjinKwon]

Seems we should specify numeric, date or timestamp at these two occurrences too

spark/R/pkg/R/SQLContext.R

Line 627 in f5317f1

#' @param partitionColumn the name of a column of integral type that will be used for partitioning

spark/python/pyspark/sql/readwriter.py

Lines 536 to 540 in a5a5da7

	:param column: the name of an integer column that will be used for partitioning;
	if this parameter is specified, then ``numPartitions``, ``lowerBound``
	(inclusive), and ``upperBound`` (exclusive) will form partition strides
	for generated WHERE clause expressions used to split the column
	``column`` evenly

LGTM otherwise

[SparkQA]

Test build #110156 has finished for PR 25687 at commit 3b03c73.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #110159 has finished for PR 25687 at commit 8935d4c.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[HyukjinKwon]

Merged to master.

[srowen]

I also backported to 2.4