Adjust the URL of the public repository, in INSTALL.md

INSTALL.md

@@ -186,7 +186,7 @@ Build VAirDraw
 > * for external users, the git repository is
 >
 >   ```
->   https://gitlab.cristal.univ-lille.fr/pirvi/vairdraw/vairdraw-public.git
+>   https://gitlab.cristal.univ-lille.fr/pirvi-public/vairdraw/vairdraw-src.git
 >   ```
 >
 > Adjust the git-clone command accordingly