Update facade docblocks

Author: taylorotwell

src/Illuminate/Support/Facades/Route.php

@@ -90,6 +90,7 @@
  * @method static \Illuminate\Routing\RouteRegistrar controller(string $controller)
  * @method static \Illuminate\Routing\RouteRegistrar domain(string $value)
  * @method static \Illuminate\Routing\RouteRegistrar middleware(array|string|null $middleware)
+ * @method static \Illuminate\Routing\RouteRegistrar missing(\Closure $missing)
  * @method static \Illuminate\Routing\RouteRegistrar name(string $value)
  * @method static \Illuminate\Routing\RouteRegistrar namespace(string|null $value)
  * @method static \Illuminate\Routing\RouteRegistrar prefix(string $prefix)