Adjusted line spacing for Garamond font

Thanks to Holger Peters [1] for raising this issue on Twitter. I would
not have caught it otherwise because I am not using `pdflatex` to work
with the package.

[1]: https://www.holger-peters.de/

Thesis.tex

@@ -72,6 +72,7 @@
 \else
   \usepackage[lf]{ebgaramond}
   \usepackage[oldstyle,scale=0.7]{sourcecodepro}
+  \singlespacing
 \fi
 
 \renewcommand{\th}{\textsuperscript{\textup{th}}\xspace}