LU-1342 test: sanity-quota test_29

LU-1342 test: sanity-quota test_29

sanity-quota test_29() needs sleep enough seconds to take into account
both service time and network latency.

Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: Ide2b321fbd104eede17eee109998d40d98fb2d30
Reviewed-on: http://review.whamcloud.com/3870
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Jay J Lan <jay.j.lan@nasa.gov>
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>