Change to https link, using the http link redirects to the changed link.

Author: HonkingGoose

book/01-introduction/sections/installing.asc

@@ -53,7 +53,7 @@ image::images/git-osx-installer.png[Git macOS installer.]
 
 You can also install it as part of the GitHub for Mac install.
 Their GUI Git tool has an option to install command line tools as well.
-You can download that tool from the GitHub for Mac website, at http://mac.github.com[].
+You can download that tool from the GitHub for Mac website, at https://desktop.github.com/[].
 
 ==== Installing on Windows