use regexp in multiparam test

Author: davidmartos96

pkgs/shelf_router/test/router_test.dart

@@ -262,16 +262,16 @@ void main() {
 
   test('can mount dynamic routes with multiple parameters', () async {
     var app = Router();
-    app.mount(r'/first/<second>/third/<fourth>/last',
-        (Request request, String second, String fourth) {
+    app.mount(r'/first/<second>/third/<fourth|\d+>/last',
+        (Request request, String second, String fourthNum) {
       var router = Router();
-      router.get('/', (r) => Response.ok('$second $fourth'));
+      router.get('/', (r) => Response.ok('$second ${int.parse(fourthNum)}'));
       return router(request);
     });
 
     server.mount(app);
 
-    expect(await get('/first/hello/third/bye/last'), 'hello bye');
+    expect(await get('/first/hello/third/12/last'), 'hello 12');
   });
 
   test('can mount dynamic routes with regexp', () async {