overlay/023: use numeric user and group IDs in getfacl

This prevents test failures if cases where, e.g., /etc/group doesn't
include the 'root' group ID.

Cc: Xiong Zhou <xzhou@redhat.com>
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Murphy Zhou <xzhou@redhat.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

tests/overlay/023

@@ -55,7 +55,7 @@ setfacl -d -m o::rwx $wkdir
 _scratch_mount
 
 # getting acls, ACL set on workdir should be cleaned
-getfacl -p $wkdir/work 2>&1 | _filter_scratch | _filter_ovl_dirs
+getfacl -n -p $wkdir/work 2>&1 | _filter_scratch | _filter_ovl_dirs
 
 # success, all done
 status=0

tests/overlay/023.out

@@ -1,7 +1,7 @@
 QA output created by 023
 # file: SCRATCH_DEV/OVL_WORK/work
-# owner: root
-# group: root
+# owner: 0
+# group: 0
 user::---
 group::---
 other::---