Change mmap rand bits as a temporary mitigation to resolve asan bug

[madolson]

There is a new change in linux kernel 6.6.6 that uses randomization of address space to harden security, but it interferes with the way ASAN works. Folks are working on a fix, but this is a temporary mitigation for us to get our CI to be green again.

See google/sanitizers#1716 for more information

See https://github.com/redis/redis/actions/runs/8305126288/job/22731614306?pr=13149 for a recent failure

[oranagra]

just to be sure i understand.
it broke because the OS image started using a new kernel, and it'll get resolved once the compiler is upgraded to a version that works around it, right?
meanwhile, are we losing anything by applying the change in this PR? i suppose not.
what do we need to watch in order to know when we need to revert this?

[sundb]

@oranagra the compiler doesn't matter, as soon as actions/runner-images#9491 is complete we can revert it.

[oranagra]

ok, but in any way i assume we're not losing anything if we forget.

[oranagra]

meanwhile, i'll mark it for backport

[enjoy-binbin]

for the record, actions/runner-images#9491 (comment) has been fixed

i tested that the code after revert can pass: https://github.com/enjoy-binbin/redis/actions/runs/8368922790