LU-10234 tests: use wait correctly in sanity-hsm test_3[4-6]

LU-10234 tests: use wait correctly in sanity-hsm test_3[4-6]

Test 34, 35 and 36 did not properly check the return code of wait
and potentially missed regressions.

Test-Parameters: trivial testlist=sanity-hsm
Signed-off-by: Quentin Bouget <quentin.bouget@cea.fr>
Change-Id: I21e8b16b55b946a8e5837549c3a3698379132e48
Reviewed-on: https://review.whamcloud.com/30102
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Dominique Martinet <dominique.martinet@cea.fr>
Reviewed-by: Henri Doreau <henri.doreau@cea.fr>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Ben Evans <bevans@cray.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>