First contribution

Created "contributions.md". Added my first PR into the file.

Author: noblesword

interns/noblesword/contributions.md

@@ -1 +1,4 @@
-
+**#1 Bug Fix**</br>
+##### Description</br>
+Initially 1.5.x was mentioned as the minimum yarn version in https://github.com/coderplex/learnplex/blob/docs/docs/prerequisites.md. But no such version exists even on the yarn page. So I have changed it to the latest stable release.<br>
+https://github.com/coderplex/learnplex/commit/7b689114f353bb6d462958880fca93c49c02912f