fix: check for Middleware manifest & chain (#1435)

* fix: add check for sortedMiddleware

* chore: prettier

* chore: double check

* chore: too much ctrl z

Author: sarahetter

package-lock.json

@@ -148,7 +148,7 @@ const plugin: NetlifyPlugin = {
 
     const middlewareManifest = await loadMiddlewareManifest(netlifyConfig)
 
-    if (!process.env.NEXT_USE_NETLIFY_EDGE && middlewareManifest.sortedMiddleware.length !== 0) {
+    if (!process.env.NEXT_USE_NETLIFY_EDGE && middlewareManifest?.sortedMiddleware?.length) {
       console.log(
         yellowBright(outdent`
           You are using Next.js Middleware without Netlify Edge Functions.