typo (#87)

Author: mikaelm12

docs/4. Add auth features.md

@@ -188,7 +188,7 @@ In this module we're going to add the capability for users to register and sign-
 
         ...
     ```
-1. Add a `bool` proprety to the page model to indicate to the page whether admin creation is currently allowed:
+1. Add a `bool` property to the page model to indicate to the page whether admin creation is currently allowed:
     ``` c#
     public bool AllowAdminCreation { get; set; }
     ```