[SPARK-13728][SQL] Fix ORC PPD test so that pushed filters can be checked.

## What changes were proposed in this pull request?
https://issues.apache.org/jira/browse/SPARK-13728

https://github.com/apache/spark/pull/11509 makes the output only single ORC file.
It was 10 files but this PR writes only single file. So, this could not skip stripes in ORC by the pushed down filters.
So, this PR simply repartitions data into 10 so that the test could pass.
## How was this patch tested?

unittest and `./dev/run_tests` for code style test.

Author: hyukjinkwon <gurwls223@gmail.com>

Closes #11593 from HyukjinKwon/SPARK-13728.