Merge branch 'exercism:main' into add-resistor-color-duo-exercise

docs/INSTALLATION.md

@@ -19,6 +19,8 @@ You may need to prefix `sudo` to the start of the command to install to a locati
 ~~~~exercism/caution
 Racket may also be available through your distribution's package manager, although it may be older than the latest Racket version.
 While you may choose to use your package manager's version now and upgrade to the current version later, as a learner you will have a much better experience if you stick to the current release available from [the official download site][racket-dl].
+
+[racket-dl]: https://download.racket-lang.org
 ~~~~
 
 ## macOS