OCPBUGS-36448: Rephrase sentence

Author: amolnar-rh

modules/ztp-image-based-upgrade-hub-cluster-guide.adoc

@@ -7,4 +7,4 @@
 If you are using {rh-rhacm-first}, your hub cluster needs to meet the following conditions:
 
 * To avoid including any {rh-rhacm} resources in your seed image, you need to disable all optional {rh-rhacm} add-ons before generating the seed image.
-* Your hub cluster must be upgraded at least to the target version before performing an image-based upgrade a target {sno} cluster.
+* Your hub cluster must be upgraded to at least the target version before performing an image-based upgrade on a target {sno} cluster.