Update policy-assignments.md

[arrerezai]

Spelling correction

[arrerezai]

@apybar, apologies, but quickly reviewing documentation for spelling before pushing may be a point to all, i.e. I am not only referring to the latest update that you've made but also to previous content that was updated by your peers. Spelling doesn't affect the technical solution or logic but makes the solution look more professional, at least in my opinion...