docs(start): fix createRouter call (#3290)

Author: Pikachews

docs/start/framework/react/build-from-scratch.md

@@ -140,6 +140,7 @@ import { routeTree } from './routeTree.gen'
 export function createRouter() {
   const router = createTanStackRouter({
     routeTree,
+    scrollRestoration: true,
   })
 
   return router
@@ -190,9 +191,7 @@ import { hydrateRoot } from 'react-dom/client'
 import { StartClient } from '@tanstack/start'
 import { createRouter } from './router'
 
-const router = createRouter({
-  scrollRestoration: true,
-})
+const router = createRouter()
 
 hydrateRoot(document, <StartClient router={router} />)
 ```

docs/start/framework/react/learn-the-basics.md

@@ -85,9 +85,7 @@ import { hydrateRoot } from 'react-dom/client'
 import { StartClient } from '@tanstack/start'
 import { createRouter } from './router'
 
-const router = createRouter({
-  scrollRestoration: true,
-})
+const router = createRouter()
 
 hydrateRoot(document, <StartClient router={router} />)
 ```