HUE-6470 [core] Adjust the z-index of the custom banner so the result table doesn't overlap

desktop/core/src/desktop/static/desktop/less/hue.less

@@ -888,3 +888,8 @@ a:visited {
 #clearNotificationHistoryModal {
   z-index: 10000;
 }
+
+.banner {
+  position: relative;
+  z-index: 1010;
+}