Spool holder 2Kg for Mk4

An adapter and holder to be able to mount 2kg spools of filament onto a Prusa Mk4 sample holder.

I printed both pieces in PLA and it seems to be working fine. But probably PETG or ASA would be better longterm.

I printed the adapter with supports but that was probably overkill in hindsight. I printed both pieces without a brim.