Display coursereg notification modal in front (#3470)

Author: EssWhyy

website/src/styles/constants.scss

@@ -180,13 +180,13 @@ $navbar-z-index: 890;
 $module-finder-search-z-index-md: 850;
 
 // navtabs and navbar should never overlap the dropdown
+$modreg-notification-z-index: 970;
 $zindex-dropdown: 910; // Bootstrap override
 $fab-z-index: 800;
 $venue-map-z-index: 760;
 $venue-detail-z-index: 750;
 $side-menu-z-index: 700;
 $side-menu-overlay-z-index: 690;
-$modreg-notification-z-index: 910;
 $timetable-warning-z-index: 200;
 $timetable-scolled-day-z-index: 120;
 $timetable-selected-cell-z-index: 110;