fix(medusa): category_id and q params for list products endpoint ld work (#4889)

Looks like during an earlier refactor, some of the categories logic wasn't ported over to the handler that works with q params. 

what:

- adds a fix that allows queries to be made on category_id when q param is passed.

Fixes https://github.com/medusajs/medusa/issues/4885

.changeset/tough-baboons-shop.md

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+---
+"@medusajs/medusa": patch
+---
+
+fix(medusa): category_id and q params for list products endpoint should work