Include product name in net-new system indices exception (#102678)

This PR includes the product value passed via the header in the
exception message for accessing net-new system indices similar to the
error message for accesing system data streams.

server/src/main/java/org/elasticsearch/indices/SystemIndices.java

@@ -530,7 +530,7 @@ public class SystemIndices {
             );
         } else {
             return new IllegalArgumentException(
-                "Indices " + Arrays.toString(names.toArray(Strings.EMPTY_ARRAY)) + " use and access is reserved for system operations"
+                "Indices " + Arrays.toString(names.toArray(Strings.EMPTY_ARRAY)) + " may not be accessed by product [" + product + "]"
             );
         }
     }