FIX: removed '#' before youtube link.

Author: yoey42

src/pages/en/tutorials/introduction-tutorials/closeout.md

@@ -30,7 +30,7 @@ nav:
         url: '/tutorials/introduction-tutorials/introduction/'
 
 ---
-# @[youtube](5A3W9LjLJos)
+@[youtube](5A3W9LjLJos)
 
 ## Name of project and Project URL on IdeaScale/Fund