fix markdown bug in hiearchy

README.md

 # SVEPM 2021 - WS5 : Extraction of medical terms from non-structured (textual) datafrom online news and social media
-## [Wednesday 24th March, 14.00-17.00](https://www.svepm2021.org/upload/pdf/SVEPM2021_WS5.pdf)
+Link to the workshop: [Wednesday 24th March, 14.00-17.00](https://www.svepm2021.org/upload/pdf/SVEPM2021_WS5.pdf).
 
 Introduction of Natural Language Processing (NLP) methods applied to health domain : an overview of terminology extraction from online news and social network (Twitter).
 
-## How to use it :
+## How to use this repository
 You can launch a jupyter notebook thank to [mybinder](https://mybinder.org/) : [![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/git/https%3A%2F%2Fgitlab.irstea.fr%2Fremy.decoupes%2Fsvepm2021-ws5-textmining/HEAD)
 
 ## Authors