Note that PR review comments should be enabled in webhook

[clubby789]

We specifically check review comments:

homu/homu/main.py

Lines 1628 to 1644 in f652a9e

	for comment in pull.iter_comments():
	if comment.original_commit_id == pull.head.sha:
	parse_commands(
	comment.body,
	comment.user.login,
	comment.user.id,
	repo_label,
	repo_cfg,
	state,
	my_username,
	db,
	states,
	sha=comment.original_commit_id,
	command_src=comment.to_json()['html_url'],
	# FIXME switch to `comment.html_url`
	# after updating github3 to 1.3.0+
	)

But the README doesn't recommend enabling this, so PR review comments are only checked on resynchronization. Ticking this box makes it work.