Actually run admin check on feature flag page

src/app/(proper_react)/redesign/(authenticated)/admin/feature-flags/page.tsx

@@ -20,7 +20,7 @@ export default async function FeatureFlagPage() {
     return redirect("/");
   }
 
-  if (!isAdmin) {
+  if (!isAdmin(session.user.email)) {
     return notFound();
   }