chore(examples): require `WORDPRESS_API_URL` to include `/graphql` (#38764)
chore(examples): require `WORDPRESS_API_URL` to include `/graphql` (#38764)

Fixes #38749

Since we are calling it `API_URL`, it sounds more correct to require including the `/graphql` rather than making `WORDPRESS_API_URL` be just the root domain in https://github.com/vercel/next.js/blob/54f87245dc8a181759a3c8065a35c7fbb1d1d329/examples/cms-wordpress/README.md?plain=1#L96


## Bug

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