Fix: typo in CONTRIBUTING.md

[Lwenz95]

Fixed a typo in the CONTRIBUTING.md file.

🚀 Description

📄 Motivation and Context

Just a minor fix, solves no problem because there is no problem

🧪 How Has This Been Tested?

It doesn't need to be tested

📷 Screenshots (if appropriate)

📦 Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

✅ Checklist

• My code follows the code style of this project(Do your best to follow code styles. If none apply just skip this).
• My change requires a change to the documentation. (I don't know)
• [x ] I have updated the documentation accordingly.