Create endpoint to reset package mappings of unreleased erratas

[javihernandez]

We need a new endpoint that can be called in order to reset package mappings of multiple unreleased erratas.
Right now we have the /errata/reset-matched-packages one, which does this for a single errata, so we need either a new one that can do multiple erratas or a single one that can handle one or many erratas.

The date argument should be added when calling the endpoint, and all records with a date higher should get their package mappings reset and regenerated.