Add change owners for Personalizer SDK (#22957)

Author: Mohit-Chakraborty

.github/CODEOWNERS

@@ -639,6 +639,10 @@ sdk/trafficmanager/Microsoft.Azure.Management.TrafficManager/            @tmsupp
 # ServiceLabel: %WebPubSub %Service Attention
 /sdk/webpubsub/  @vicancy @JialinXin
 
+# ServiceLabel: %Personalizer %Service Attention
+# PRLabel: %Personalizer
+/sdk/personalizer/ @ormichae @Mohit-Chakraborty
+
 # ######## Management Plane ########
 
 /**/*Management*/                               @m-nash @fengzhou-msft @archerzz @ArcturusZhang @yungezz