ui_report: Remove class when hiding the status element.

It is important to remove the class when hiding the status
element to make sure that when showing status again by calling
some other function than ui_report.message, for example using
loading.make_indicator, the status text should not be styled
as per the class used previously.

One example can be that "Saving" text in indicator can be shown
in "red" color, used for showing errors, if previously an error
response was showed in that status element.

web/src/ui_report.ts

@@ -27,7 +27,7 @@ export function message(
         .fadeTo(0, 1);
     if (remove_after !== undefined) {
         setTimeout(() => {
-            $status_box.fadeOut(400);
+            $status_box.fadeOut(400, () => $status_box.removeClass(cls));
         }, remove_after);
     }
     $status_box.addClass("show");