Update README.md

README.md

@@ -81,7 +81,7 @@ CMD gunicorn -b :$PORT mysite.wsgi
 
 ### Setup Gitlab CI
 
-At the root of your git repository create a `.gitlab-ci.yaml` file.
+At the root of your git repository create a `.gitlab-ci.yml` file.
 
 We will use a special docker image which contain the docker binary.
 We will attach to the running docker daemon in order to build the image.