Fixed express router reference after routes.yaml refresh

refs #9601, refs #9744

- the express router reference wasn't updated fully
- the stack was the old router stack when you have uploaded a new routes.yaml file
  - this has caused e.g. that new redirects for channels/collections didn't work after the upload

core/server/services/routing/ParentRouter.js

@@ -146,6 +146,8 @@ class ParentRouter extends EventEmitter {
     }
 
     isRedirectEnabled(routerType, slug) {
+        debug('isRedirectEnabled', this.name, this.route && this.route.value, routerType, slug);
+
         if (!this.data || !Object.keys(this.data.router)) {
             return false;
         }

core/server/web/site/app.js

@@ -36,6 +36,10 @@ var debug = require('ghost-ignition').debug('blog'),
 
 let router;
 
+function SiteRouter(req, res, next) {
+    router(req, res, next);
+}
+
 module.exports = function setupSiteApp(options = {}) {
     debug('Site setup start');
 
@@ -128,11 +132,6 @@ module.exports = function setupSiteApp(options = {}) {
     debug('General middleware done');
 
     router = siteRoutes(options);
-
-    function SiteRouter(req, res, next) {
-        router(req, res, next);
-    }
-
     setPrototypeOf(SiteRouter, router);
 
     // Set up Frontend routes (including private blogging routes)
@@ -150,6 +149,7 @@ module.exports = function setupSiteApp(options = {}) {
 module.exports.reload = () => {
     // https://github.com/expressjs/express/issues/2596
     router = siteRoutes({start: true});
+    setPrototypeOf(SiteRouter, router);
 
     // re-initialse apps (register app routers, because we have re-initialised the site routers)
     apps.init();