Fix lists JSON payload

Co-authored-by: RD WebDesign <github@rdwebdesign.com.br>
Signed-off-by: Dominik <DL6ER@users.noreply.github.com>

scripts/pi-hole/js/groups-lists.js

@@ -397,7 +397,7 @@ function initTable() {
           var ids = [];
           $("tr.selected").each(function () {
             // ... add the row identified by "data-id".
-            ids.push($(this).attr("data-id"));
+            ids.push({ item: $(this).attr("data-id") });
           });
           // Delete all selected rows at once
           delGroupItems("list", ids, table);