Add possibility to set the font-family: "Inter" for variable font

[emattias]

We want to be able to do font-family: "Inter" to use the variable font instead of having to do font-family: "InterVariable"

Something like:

@use "~inter-ui/variable" with (
  $inter-font-family: "Inter"
);

[philipbelesky]

Hi @emattias, thanks for the feedback and sorry for my very delayed reply. I would like to get to this eventually, but - in the meantime - I'd be happy to accept a PR for it.