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.
# Abstraction layer for HTTP2 with ESP_TLS This component contains an abstraction layer which exposes simpler set of APIs combining `nhttp` (HTTP/2 C Library) and `esp_tls` components.
idf.py add-dependency "espressif/sh2lib^0.1.0"