Gitaly cgroups: Delete gitaly-0 directory from cgroup hierarchy root
Overview
In https://gitlab.com/gitlab-com/gl-infra/reliability/-/issues/16234#note_1082390476 we still saw a child cgroup called gitaly-0
not being deleted. This is because we check for the process of the id and pid=0
doesn't exist and probably ends up never reaching the signal part where we remove the file
Edited by Steve Xuereb