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_3fbe6c8a-ca51-440a-b60e-12f4aca0569a_yankable=1.0.0:cmp_ex"