cgroups v2 detection fails in containerized environment about clickhouse HOT 1 CLOSED

I made a fix but then realized something.

The cgroups v2 docs say

Top-down Constraint
~~~~~~~~~~~~~~~~~~~

Resources are distributed top-down and a cgroup can further distribute
a resource only if the resource has been distributed to it from the
parent.  This means that all non-root "cgroup.subtree_control" files
can only contain controllers which are enabled in the parent's
"cgroup.subtree_control" file.  A controller can be enabled only if
the parent has the controller enabled and a controller can't be
disabled if one or more children have it enabled.

In other words, if like here the top-level cgroups.subtree_control file (/sys/fs/cgroup/cgroup.subtree_control) is empty, then all child cgroups.subtree_control files will be empty too. So while my fix (which checks the existence of "memory" recursively ascending, starting from the bottom-most file) is generally useful, it won't help with this issue. I suspect there is a configuration error with Docker - because why else should all cgroups controllers be disabled?

EDIT: Please ignore what I wrote above, here is a fix that will solve this issue: #62903

from clickhouse.