LU-10870 tests: disable sanityn test 40a

LU-10870 tests: disable sanityn test 40a

If sanityn 40a is run several times there is a good chance the
test will fail. Disable the test until a solution is presented.
Currently Oleg's rocky8 setup will easily reproduce this
problem.

Test-Parameters: trivial testlist=sanityn
Change-Id: I0bdff999ecdf2481c2bd9eda6c4fc8b1cacd08d5
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/58795
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Timothy Day <timday@amazon.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>