LU-8999 test: check chown result

LU-8999 test: check chown result

For test_38 in sanity-quota, the chown operation should be
checked whether it succeeds or not. the patch also collects
the output of quota users if the test failed.

Change-Id: I6c04f9519f3f097af7126064380faf1bdc4fff6a
Signed-off-by: Hongchao Zhang <hongchao.zhang@intel.com>
Reviewed-on: https://review.whamcloud.com/30243
Tested-by: Jenkins
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Jian Yu <jian.yu@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>