Centos 8 Stream removed the capabilities to open raw sockets from the
ping binary and added new sysctl default to allow an unprivileged user
to send ping request. This sysctl was not inherited by the
amphora-haproxy namespace. Add it explicitly to our sysctl list.
Story 2009953
Task 44911
Change-Id: I499bdd5edc23b602495a9b2b9f22baf9547261d5
(cherry picked from commit cbf79c5627)
(cherry picked from commit 8cd697e8bf)