Fixing heapsort inclusion.

Author: Clément

source/lectures/misc/sorting.md

@@ -45,7 +45,7 @@ We first define some helper methods:
 and then leverage the heap structure to sort:
 
 ```
-!include`snippetStart="// Heapsort Algorithm", snippetEnd="// Done with heapsort Algorithm` code/projects/Sorting/Sorting/Sorting.cs
+!include`snippetStart="// Heapsort Algorithm", snippetEnd="// Done with heapsort Algorithm"` code/projects/Sorting/Sorting/Sorting.cs
 ```
 
 Note that `PercDown` builds a *max heap*: once the values are "pre-sorted **greater value first**", removing the first one to move it to the *end* of the list makes the list sorted from smallest to greatest value once we are done.