Fix the separator

Author: Kaelig Deloumeau-Prigent

README.md

@@ -22,7 +22,8 @@ Download the most recent version of [Sketch](https://www.sketchapp.com/).
 1. [Download the Design System Zip](https://www.lightningdesignsystem.com/resources/downloads/)
 2. Find the fonts located in the `/assets/fonts` directory
 3. Install the fonts on your system
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 ## Contribute!
 The SLDS team welcomes your help in maintaining and growing this UI kit.