Add fine Font EB Garamond

[xaviduds]

https://fonts.google.com/specimen/EB+Garamond
This is a font for fine text, one that I really like. If i did the job of making a PR with that font in the /files/fonts dir:

1. Would that be enough for it to be built into typst?
2. Would the PR get accepted?

[laurmaedje]

The current built-in fonts are the three default fonts (text, raw, math) plus New Computer Modern as a small bonus for people coming from LaTeX. We don't want to add further fonts to the binary as that would bloat it and there is no clear line where to stop.