fix: imports (part 2/2) (#13520)

Completes https://github.com/payloadcms/payload/pull/13513

That PR fixed it for the `admin` suite, but I had also encountered the
same issue in `live-preview`.

When searching for instances, I found others with the same pattern
within packages, which I took the opportunity to fix in case the same
error occurs in the future.

test/helpers/bootAdminPanel.mjs

@@ -2,7 +2,7 @@ import { createServer } from 'http'
 import next from 'next'
 import { parse } from 'url'
 
-const actualNext = next.default || next
+const actualNext = 'default' in next ? next.default : next
 export const bootAdminPanel = async ({ port = 3000, appDir }) => {
   const serverURL = `http://localhost:${port}`
   const app = actualNext({