Update CONTRIBUTING.md

Co-Authored-By: Stefan Schweter <stefan.schweter@bsb-muenchen.de>

CONTRIBUTING.md

@@ -83,7 +83,7 @@ A world-class feature request addresses the following points:
 If your issue is well written we're already 80% of the way there by the time you
 post it.
 
-We have added **templates** to guide you in the process of adding a new example script for training or testing the models in the library. You can find then in the [`templates`](./templates) folder.
+We have added **templates** to guide you in the process of adding a new example script for training or testing the models in the library. You can find them in the [`templates`](./templates) folder.
 
 ## Start contributing! (Pull Requests)