fix: typo

Author: nicobao

CONTRIBUTING.md

@@ -14,7 +14,7 @@ After configuring the signing key, commit using `git commit -s` or simply [confi
 
 ## FLA
 
-Every contributors must sign our iteration of the [Free Software Foundation Europe's Fiduciary Licensing Agreement](https://cla-assistant.io/zkorum/zkorum). Click on the link to sign it with your GitHub account.
+Every contributor must sign our iteration of the [Free Software Foundation Europe's Fiduciary Licensing Agreement](https://cla-assistant.io/zkorum/zkorum). Click on the link to sign it with your GitHub account.
 
 What does it do? In short, it is a normalized contract that allows us to change the license of your code to any other OSI-approved and FSF-approved free and open-source license. You delegate to us the responsibility to defend against eventual license misuse. But it does NOT allow us to sell your GPL code under a proprietary license (dual licensing), like every other CLA does. The FLA is in use by large free software projects such as KDE for example.