On html-collect-pages, do callbacks

def call_html_collect_pages(cls, kb_app, sphinx_app: Sphinx):
        """ On html-collect-pages, do callbacks"""

        EventAction.get_callbacks(kb_app,
                                  SphinxEvent.HCP)
        for callback in EventAction.get_callbacks(kb_app,
                                                  SphinxEvent.HCP):
            yield callback(kb_app, sphinx_app)