docs(contributing.md): fix typo (#128)

Author: lauthieb

CONTRIBUTING.md

@@ -39,7 +39,7 @@ When you are opening an issue, please be sure to report as much information as y
 If you are a dev and you want to directly fix a problem or implement a new feature... you are the best one ! :clap:
 To propose any change you have to submit us a [Pull Request](https://help.github.com/articles/about-pull-requests/)
 
-The workflow we are using the one-pay project is:
+The workflow we are using is:
 
 1. Fork this repository (as you don't have a direct write access to the main one).
 2. Create your code, `Commit` and `Push the code` on your forked repo