Yunohost templating doesn't like @__NAME____proxy because `reverseproxy__2__proxy` will evaluate __2__ to $2
or @__NAME__@proxy because ynh_replace_vars uses @ as sed delimiter
and ynh_replace_vars really hates multiline blocks... Using actual newlines in string produces a sed unclosed delimiter error,
while using \n gets them double escaped to some weird output that crashed nginx.