Updates the LICENSE file (to re-trigger Licensee hook)

[HorlogeSkynet]

Description

Simple LICENSE file update.

Reason and / or context

GPLv3 was not detected on the project repository.

How has this been tested ?

It has not, let's see if it works out.

Types of changes :

• Bug fix (non-breaking change which fixes an issue)
• Typo / style fix (non-breaking change which improves readability)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Meta

Checklist :

• [IF NEEDED] I have updated the README.md file accordingly ;
• [IF NEEDED] I have updated the test cases (which pass) accordingly ;
• My change looks good ;
• I agree that my code may be modified in the future ;
• My code follows the code style of this project (PEP8).