Today when running in production mode the bootstrap checks are
completely unforgiving. But there are cases where an end-user might not
have the ability to modify some of the system-level settings that cause
the bootstrap checks to trip (e.g., guest settings that are inherited
from a host and can not be modified). This commit adds a setting that
allows system-level bootstrap checks to be ignored for these
end-users. We classify certain bootstrap checks into system-level checks
and only those bootstrap checks will be ignored if this flag is
enabled. All other bootstrap checks are still subject to being enforced
if the user is in production mode. We will still log warnings for these
bootstrap checks because the end-user does still need to be made aware
that they are running in a configuration that is less-than-ideal from a
resiliency perspective.

Relates elastic#18088