[SPARK-25629][TEST] Reduce ParquetFilterSuite: filter pushdown test time costs in Jenkins

[wangyum]

What changes were proposed in this pull request?

Only test these 4 cases is enough:

spark/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetWriteSupport.scala

Lines 269 to 279 in be2238f

	// Standard mode, 1 <= precision <= 9, writes as INT32
	case false if precision <= Decimal.MAX_INT_DIGITS => int32Writer
	// Standard mode, 10 <= precision <= 18, writes as INT64
	case false if precision <= Decimal.MAX_LONG_DIGITS => int64Writer
	// Legacy mode, 1 <= precision <= 18, writes as FIXED_LEN_BYTE_ARRAY
	case true if precision <= Decimal.MAX_LONG_DIGITS => binaryWriterUsingUnscaledLong
	// Either standard or legacy mode, 19 <= precision <= 38, writes as FIXED_LEN_BYTE_ARRAY
	case _ => binaryWriterUsingUnscaledBytes

How was this patch tested?

Manual tests on my local machine.
before:

- filter pushdown - decimal (13 seconds, 683 milliseconds)

after:

- filter pushdown - decimal (9 seconds, 713 milliseconds)

[SparkQA]

Test build #96962 has finished for PR 22636 at commit e40d79c.

• This patch fails to build.
• This patch merges cleanly.
• This patch adds no public classes.

[wangyum]

retest this please

[SparkQA]

Test build #96965 has finished for PR 22636 at commit e40d79c.

• This patch fails due to an unknown error code, -9.
• This patch merges cleanly.
• This patch adds no public classes.

[wangyum]

retest this please

[SparkQA]

Test build #96976 has finished for PR 22636 at commit e40d79c.

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

[gatorsmile]

The time reduction is not obvious. Let us keep this unchanged?

[HyukjinKwon]

Yea, it is not obvious and only few seconds - might not be so worth. But looks improvement because it fixes the test cases to test what the previous PR targeted. Wouldn't it be better just to go ahead rather then close this since the PR is already open?

[HyukjinKwon]

@wangyum, can you reopen this? I don't think we should just close this. Fixing tests to actually test what the previous change targeted sounds definitely an improvement although it's minor. I wouldn't encourage to fix those but at least I would go ahead for this one since the fix is already proposed.

[SparkQA]

Test build #97362 has finished for PR 22636 at commit e40d79c.

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

[HyukjinKwon]

Merged to master.