fix linagora/Twake#2799

[Clem-]

Plugins Add : repo name must be lowercase

Description

Convert to lowercase the foldername that is used as the repository name.

Related Issue

Plugins Add : repo name must be lowercase #2799

Motivation and Context

Can't add a plugin with a non lowercase repo name

How Has This Been Tested?

Running the command of the issue is now working

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 change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added the Signed-off-by statement at the end of my commit message.