Fixes LaTeX compile error with FontAwesome font

[maxgrim]

The \setfontfamily\FA command causes a compilation error using xelatex. This small fix makes sure that the document compiles again.

The compilation error:

$ xelatex resume.tex
...
! LaTeX3 Error: Command '\FA' already defined!

For immediate help type H <return>.
 ...

l.166 \newfontfamily
                    \headerfont[
?

[OJFord]

Thank you - I think many of us have made this or similar fixes over the years as posquit0's had other priorities. I have push access now to help maintain Awesome-CV; so I went with my old PR for this (#235/#344) for no reason other than my own familiarity, that I know it's been working for me.

Please do ping me/open another PR if something's still not right or I missed something though! Cheers.