Language: Minor: Fix language variable to use existing one - refs BT#21957

Author: NicoDucou

public/main/admin/statistics/index.php

@@ -768,7 +768,7 @@
 
             $table->actionButtons = [
                 'export' => [
-                    'label' => get_lang('Export As XLS'),
+                    'label' => get_lang('Export to XLS'),
                     'icon' => Display::getMdiIcon(ActionIcon::EXPORT_SPREADSHEET,'ch-tool-icon'),
                 ],
             ];