LU-9620 tests: test race between pool_list and pool_remove

LU-9620 tests: test race between pool_list and pool_remove

Test ost-pools/test_27 added to test race between
pool_list and pool_remove.

Change-Id: I8497836dd6e8b2c20ade3626b7a1f84b98f3a94f
Seagate-bug-id: MRP-3629
Signed-off-by: Jadhav Vikram <jadhav.vikram@seagate.com>
Reviewed-by: Ashish Purkar <ashish.purkar@seagate.com>
Reviewed-by: Andriy Skulysh <andriy.skulysh@seagate.com>
Tested-by: Elena V. Gryaznova <elena.gryaznova@seagate.com>
Reviewed-on: https://review.whamcloud.com/27505
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>