api: acme: deprecate tos endpoint in favor of new meta endpoint

api: acme: deprecate tos endpoint in favor of new meta endpoint

The ToS endpoint ignored data that is needed to detect if EAB needs to
be used. Instead of adding a new endpoint that does the same request,
the tos endpoint is deprecated and replaced by the meta endpoint,
that returns all information returned by the directory.

Signed-off-by: Folke Gleumes <f.gleumes@proxmox.com>