Refs #6078, do not pivot table when getting siteSummary data.

plugins/CoreVisualizations/Visualizations/HtmlTable.php

@@ -64,7 +64,8 @@ class HtmlTable extends Visualization
                 'filter_offset' => 0,
                 'period'        => $period,
                 'showColumns'   => implode(',', $this->config->columns_to_display),
-                'columns'       => implode(',', $this->config->columns_to_display)
+                'columns'       => implode(',', $this->config->columns_to_display),
+                'pivotBy'       => ''
             ));
 
             $dataTable = $request->process();