test: regenerate manifests with chrony stages

Regenerate all manifests that used the old chrony stage options with the
'timeservers' field.  This is now replaced by the 'servers' field, which
is a slice of objects with a 'hostname' field instead of a slice of
strings.

test/data/manifests/rhel_7-x86_64-qcow2_customize-boot.json

@@ -1714,8 +1714,10 @@
           {
             "type": "org.osbuild.chrony",
             "options": {
-              "timeservers": [
-                "time.example.com"
+              "servers": [
+                {
+                  "hostname": "time.example.com"
+                }
               ]
             }
           },