**What**
When both sides of a many to many relationship do not define the mapped by option, it leads to misconfigured relations and a malformed SQL query. (ref. https://github.com/medusajs/medusa/issues/9075)
- When both mapped by are not defined, infer look up to try to identify the missing configuration if any
- Disallow defining many to many only on one side
a9b559ab2e