[IMP] website_slide: allow to edit comment

When a portal user post a message to review a channel, we
want to allow him to edit its own comment and rating.
This commit modifies the special check access method in
portal to extract the security check and reuse it to
allow user to update its comment on slide.channel only.
We decided to reuse existing widget (new rating popup
composer) to do the message modification.

Task-1902304