edit contributing.md

doganoo · doganoo · commit 28b9b0fd1c0b · 2019-10-07T18:52:09.000+02:00
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -16,3 +16,5 @@ Please note we have a code of conduct, please follow it in all your interactions
 ````
 @author Copyright (c) year, Firstname Lastname <mail [at] example.com>
 ````
+
+4. Unit tests are required! Please add or extend unit tests. Untested code and/or skips are not allowed! 
