README.md: Fix and remove links

Author: bzg

README.md

@@ -1,7 +1,6 @@
-[![img](https://img.shields.io/badge/code.gouv.fr-contributif-blue.svg)](https://code.gouv.fr/documentation/#/publier.md)
+[![img](https://img.shields.io/badge/code.gouv.fr-contributif-blue.svg)](https://code.gouv.fr/documentation/#quels-degres-douverture-pour-les-codes-sources)
 [![Software License](https://img.shields.io/badge/Licence-MIT%2C%20Licence%20Ouverte-orange.svg)](https://github.com/codegouvfr/codegouvfr-website/tree/main/LICENSES)
 
-![build-preprod](https://img.shields.io/github/actions/workflow/status/codegouvfr/codegouvfr-website/preproduction.yml?label=Deploiement%20en%20préprod)
 ![build-prod](https://img.shields.io/github/actions/workflow/status/codegouvfr/codegouvfr-website/production.yml?label=Deploiement%20en%20prod)
 
 # Site code.gouv.fr