LU-14824 test: sanity 413a/b unlink timeout

LU-14824 test: sanity 413a/b unlink timeout

Unlinking remote/striped directories is slow on zfs system, limit
total directory number for 1-stripe directory test in 413a/b on zfs
system, and don't test striped directory to avoid timeout.

Also limit total stripe object count to avoid timeout.

Test-Parameters: trivial
Test-Parameters: mdscount=2 mdtcount=4 fstype=ldiskfs testlist=sanity env=ONLY="413a 413b",ONLY_REPEAT=50
Test-Parameters: mdscount=2 mdtcount=4 fstype=zfs testlist=sanity env=ONLY="413a 413b",ONLY_REPEAT=50
Signed-off-by: Lai Siyao <lai.siyao@whamcloud.com>
Change-Id: Ie116e6df5aee3877ed9f093f58e7bd71f6c6d9d5
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/45955
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>