[Docs] Remove the 'new' keyword from the GET function sample code. (v…

…ercel#71671)

The json() method returns a Response object, so remove the new keyword.

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Co-authored-by: JJ Kasper <[email protected]>

docs/02-app/02-api-reference/02-file-conventions/route.mdx

@@ -7,13 +7,13 @@ Route Handlers allow you to create custom request handlers for a given route usi
 
 ```ts filename="route.ts" switcher
 export async function GET() {
-  return new Response.json({ message: 'Hello World' })
+  return Response.json({ message: 'Hello World' })
 }
 ```
 
 ```js filename="route.js" switcher
 export async function GET() {
-  return new Response.json({ message: 'Hello World' })
+  return Response.json({ message: 'Hello World' })
 }
 ```