log-rolling-itest: delete test files when test ends
log-rolling-itest: delete test files when test ends

By not inheriting from the KuduTest fixture, this test didn't clean up
after itself. Normally this is caught in build-and-test.sh by the
TEST_TMPDIR contents check, but precommit jobs use dist-test so the check
only looks at local files.

Change-Id: Ia099401229bbb1d0e3bdf0580c50ae78e49e4b0e
Reviewed-on: http://gerrit.cloudera.org:8080/7100
Tested-by: Kudu Jenkins
Reviewed-by: David Ribeiro Alves <dbbafdb4f25eb0c1ff3facf0e5f2f27705055af1@gmail.com>

InspurUSA/kudu,cloudera/kudu,helifu/kudu,EvilMcJerkface/kudu,InspurUSA/kudu,andrwng/kudu,helifu/kudu,InspurUSA/kudu,helifu/kudu,cloudera/kudu,cloudera/kudu,cloudera/kudu,cloudera/kudu,helifu/kudu,andrwng/kudu,helifu/kudu,EvilMcJerkface/kudu,InspurUSA/kudu,InspurUSA/kudu,andrwng/kudu,helifu/kudu,InspurUSA/kudu,helifu/kudu,InspurUSA/kudu,helifu/kudu,cloudera/kudu,cloudera/kudu,andrwng/kudu,andrwng/kudu,andrwng/kudu,cloudera/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,cloudera/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,helifu/kudu,InspurUSA/kudu,andrwng/kudu,InspurUSA/kudu,andrwng/kudu,andrwng/kudu