LU-13997 tests: sanity/418 to cancel all client locks

LU-13997 tests: sanity/418 to cancel all client locks

verify idea about dirty client's data

Lustre-change: https://review.whamcloud.com/44803
Lustre-commit: TBD (from 42a090928b36bc14d8cb9a73a7f5b719eff38a2e)

Test-Parameters: trivial
Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Change-Id: Ifef58a98b26c7790274d2a57aa52e4475e923dd0
Reviewed-on: https://review.whamcloud.com/44936
Reviewed-by: James Nunez <jnunez@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>