Better explain how to update the tutorials list (#302)

Co-authored-by: Michael R. Crusoe <[email protected]>

Author: Fienne

src/tutorials.md

@@ -2,9 +2,7 @@
 
 % https://github.com/common-workflow-language/user_guide/issues/160
 
-This is a list to tutorials provided by the CWL community. Send a
-[pull request](https://github.com/common-workflow-language/user_guide/)
-if you would like to add another tutorial to the list.
+This is a list of tutorials provided by the CWL community. Use the `Edit this page` link in the menu if you would like to add another tutorial to the list.
 
 ## Beginner Tutorials