IMPALA-5009: Clean up test_insert_parquet.py
IMPALA-5009: Clean up test_insert_parquet.py

Replace make_tmp_dir with py.test's own tmpdir

Change-Id: Ia84c78d7ff74cc7fdb3d782060caa5e52d0cd7d2
Reviewed-on: http://gerrit.cloudera.org:8080/7518
Reviewed-by: David Knupp <6014aa7b8711b3b616d04da7c5083e463b5c51c9@cloudera.com>
Tested-by: Impala Public Jenkins

cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala