Set body background color in RedirectComponent styles to use secondary theme color

frontend/src/app/shared-components/redirect/redirect.component.scss

@@ -6,3 +6,7 @@
   font-family: system-ui, -apple-system, "Segoe UI", Roboto;
   color: #555;
 }
+
+body {
+  background-color: var(--color-secondary);
+}