update url

Author: EddyCMWF

_config.yml

@@ -17,8 +17,8 @@ latex:
 
 # Information about where the book exists on the web
 repository:
-  url: https://github.com/ecmwf-training/jupyter-template  # Online location of your book
-  branch: main  # Which branch of the repository should be used when creating links (optional)
+  url: https://github.com/ecmwf-training/c3s-training-submodule-sat-obs-land  # Online location of your book
+  branch: develop  # Which branch of the repository should be used when creating links (optional)
 
 # Add GitHub buttons to your book
 # See https://jupyterbook.org/customize/config.html#add-a-link-to-your-repository