The example of https://grafana.com/docs/k6/latest/javascript-api/jslib/httpx/batch/ uses a depecated library https://jslib.k6.io/expect/0.0.4/index.js
This library does not show any deprecated message. It has no documentation. The link to the documention on the main lib page fails.
On github the lib is marked as deprecated. ChaiJS is suggested as a replacement.
But since k6 1.2.0 this may be deprecated as well. It seems that you are moving to k6-jslib-testing.
All 3 libs offer different functionalies and APIs
Please update the example and the link in the main lib page