Simplify middleware examples (#8176)

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>
Co-authored-by: Paul Valladares <85648028+dreyfus92@users.noreply.github.com>

src/content/docs/en/guides/middleware.mdx

@@ -18,10 +18,10 @@ Middleware also allows you to set and share request-specific information across
 2. Inside this file, export an [`onRequest()`](/en/reference/api-reference/#onrequest) function that can be passed a [`context` object](#the-context-object) and `next()` function. This must not be a default export.
 
     ```js title="src/middleware.js"
-    export function onRequest ({ locals, request }, next) {
+    export function onRequest (context, next) {
         // intercept data from a request
         // optionally, modify the properties in `locals`
-        locals.title = "New title";
+        context.locals.title = "New title";
 
         // return a Response or the result of calling `next()`
         return next();
@@ -58,11 +58,11 @@ This `locals` object is forwarded across the request handling process and is ava
 You can store any type of data inside `locals`: strings, numbers, and even complex data types such as functions and maps.
 
 ```js title="src/middleware.js"
-export function onRequest ({ locals, request }, next) {
+export function onRequest (context, next) {
     // intercept data from a request
     // optionally, modify the properties in `locals`
-    locals.user.name = "John Wick";
-    locals.welcomeTitle = () => {
+    context.locals.user.name = "John Wick";
+    context.locals.welcomeTitle = () => {
         return "Welcome back " + locals.user.name;
     };