Villager profession translation keys do not include namespaces

The translation key used for villager professions is of the form: entity.minecraft.villager.<profession>. Because of this, two villager professions with IDs of the same path but different namespaces (such as foo:developer and bar:developer) will have the same translation key, entity.minecraft.villager.developer.

This is inconsistent with other registries' translation keys in that it does not have a namespace, and less importantly, is not top-level (villager_profession.<namespace>.<path>).

Steps to reproduce

1. Execute the following command: /tellraw @s {"translate":"entity.minecraft.villager.librarian"}
2. Notice that the text is translated, despite the translation key not including a namespace for the minecraft:librarian identifier.