refactor: Delete a lot of unused and duplicate code in Server and WebhookServer (#5080)

* store n8n version string in a const and use that everywhere

* reduce code duplication between Server and WebhookServer

* unify redis checks

* fix linting

packages/cli/src/middlewares/cors.ts

@@ -1,8 +1,7 @@
-import { inDevelopment } from '@/constants';
 import type { RequestHandler } from 'express';
 
 export const corsMiddleware: RequestHandler = (req, res, next) => {
-	if (inDevelopment && 'origin' in req.headers) {
+	if ('origin' in req.headers) {
 		// Allow access also from frontend when developing
 		res.header('Access-Control-Allow-Origin', req.headers.origin);
 		res.header('Access-Control-Allow-Credentials', 'true');