EX-8253 tests: skip sanity-scrub/4e until fixed

EX-8253 tests: skip sanity-scrub/4e until fixed

Subtest 18 is failing about 1/5 of sanity-scrub runs, after test_4e
was landed.  Disable test_4e to see if that fixes the issue.

Test-Parameters: trivial
Test-Parameters: testlist=sanity-scrub,sanity-scrub,sanity-scrub
Test-Parameters: testlist=sanity-scrub,sanity-scrub,sanity-scrub
Test-Parameters: testlist=sanity-scrub,sanity-scrub,sanity-scrub
Test-Parameters: testlist=sanity-scrub,sanity-scrub,sanity-scrub
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: Ia8f1bd9dbf0fdbfabf79b1ead63a0421a8892c82
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/52564
Reviewed-by: Alex Deiter <alex.deiter@gmail.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>