Add tip to use custom fonts in Quarto.

[olivroy]

Add a tip on how to use custom fonts with Quarto and Rmd documents.

Without those, custom fonts are not rendered in Qmd or Rmd documents (at least on Windows, so I thought it would be interesting to mention this here)

Change link to edit this page to the repo!

I would suggest also to add the link to the github homepage https://z3tt.github.io/graphic-design-ggplot2 in the about section

Also a typo that I caught on the fly I prefer to dave -> I prefer to save