Fix line formatting

Author: shonfeder

README.org

@@ -45,4 +45,4 @@ time (i.e. a few hours or more) to find a good solution.
 Solutions are written targeting the [[https://github.com/LPCIC/elpi][Elpi]] dialect and tested by running with
 Elpi.
 
-[[file:solutions/lists.mod][- Lists]]
+- [[file:solutions/lists.mod][Lists]]