Fix upstream and OKD builds (#1222)

PR #1099 broke upstream and OKD builds as it added a dependency on
rsync.  quay.io/centos/centos:stream9 image does not ship rsync
by default.

Once we can use the new golang's recursive copy (CopyFS) functionality
in go 1.23 (golang/go#62484), use it and
remove the dependency on rsync.

Co-authored-by: Jiri Mencak <jmencak@users.noreply.github.com>

Author: jmencak

hack/dockerfile_install_support.sh

@@ -3,7 +3,7 @@
 set -euo pipefail
 set -o xtrace
 
-INSTALL_PKGS="nmap-ncat procps-ng pciutils"
+INSTALL_PKGS="nmap-ncat procps-ng pciutils rsync"
 
 # TuneD pre-installation steps
 cp -r /root/assets/bin/* /usr/local/bin