Fix typo

content/getting-started/index.md

@@ -11,7 +11,7 @@ AIMS Desktop can be downloaded from https://desktop.aims.ac.za/download.
 AIMS Desktop is a large download (over 3GB), if you're reading this from a mobile connection,
 you might want to download it on a broadband connection instead.
 
-## Preperation
+## Preparation
 
 AIMS Desktop installs a new operating system to your computer. It can be installed alongside
 an existing system such as Microsoft Windows, Apple macOS, BSD or another GNU/Linux system.