You are using staging server - a separate instance of the ESP Component Registry that allows you to try distribution tools and processes without affecting the real registry.
To create a project from this example, run:
idf.py create-project-from-example "test_component_manager/test_a6367521-7e60-4a63-a84a-2fef978f0f56_yankable=1.0.0:cmp_ex"