doc(tutorials): add a link to museum demo source code, and correct a typo.

doc/tutorials/museum/index.rst

@@ -14,13 +14,17 @@ present museums from French Ministry of Culture data, available here_.
 .. _here: https://data.culture.gouv.fr/explore/dataset/liste-et-localisation-des-musees-de-france/export/
 
 First, we will start with installation and creation of our website, and a short presentation of
-out of the box CubicWeb functionnalities. Then, we will see how to enhance our views using Jinja2
+out of the box CubicWeb functionalities. Then, we will see how to enhance our views using Jinja2
 templates or React components to have a better looking site. Finally, we will see how to manage
 more data, and how to serialize them in RDF.
 
 At the end of this tutorial, you will have a website giving information about all France's
 museums, describes them in RDF and present them on a map.
 
+You can find the code of the finished tutorial in our forge_.
+
+.. _forge: https://forge.extranet.logilab.fr/cubicweb/cubes/tuto/
+
 .. toctree::
    :maxdepth: 2