Use empty list of projects to avoid attempting to iterate over None

serena_config.template.yml

@@ -31,4 +31,4 @@ gui_log_level: 20
 # By default, the project's name will be the name of the directory containing the project, but you may change it
 # by changing the entry in the (autogenerated) `.serena/project.yml` file.
 # Note: make sure there are no name collisions in the names of registered projects
-projects:
+projects: []