LU-17151 tests: increase sanity/411b memory limit

LU-17151 tests: increase sanity/411b memory limit

This test fails most of the time when run using
arm clients. It seems like the cgroup memory limit
was increased in a past revision for a similar issue.
Increase it a bit more for aarch64. Increase it a
smaller amount for x86.

Also, add some better logging for some other issues.

There's likely a better fix for this, but hopefully
this will let the test pass and provide some value
without having to do a full revert.

Fixes: 8aa231a99 ("LU-16713 llite: writeback/commit pages under memory pressure")
Test-Parameters: trivial
Test-Parameters: testgroup=review-ldiskfs-arm testlist=sanity env=ONLY=411b,ONLY_REPEAT=50
Test-Parameters: clientdistro=el8.7 testlist=sanity env=ONLY=411b,ONLY_REPEAT=50
Test-Parameters: clientdistro=el9.1 testlist=sanity env=ONLY=411b,ONLY_REPEAT=50
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: If850077c0d7f6466082433776d370d24eee9736c