Revert "erp5: Disable promises for Python3 until ERP5 has been ported."

This reverts commit 6c399134.

stack/erp5/buildout.hash.cfg

@@ -86,7 +86,7 @@ md5sum = 0ac4b74436f554cd677f19275d18d880
 
 [template-zope]
 filename = instance-zope.cfg.in
-md5sum = 9e6440425167a506bd473a3697eaa9e6
+md5sum = 7620c136fda8eb7424f80f0e24963cdf
 
 [template-balancer]
 filename = instance-balancer.cfg.in

stack/erp5/instance-zope.cfg.in

@@ -367,17 +367,11 @@ instance-home = ${directory:instance}
 port = {{ port }}
 
 [{{ section("promise-" ~ name) }}]
-{% if six.PY3 -%}
-# Disable the promise in Python 3. ERP5 is not compatible with Python 3 yet, so
-# the promise would always fail.
-recipe =
-{% else -%}
 <= monitor-promise-base
 promise = check_socket_listening
 name = {{ name }}.py
 config-host = {{ ipv4 }}
 config-port = {{ port }}
-{% endif -%}
 
 {% if use_ipv6 -%}
 [{{ zope_tunnel_section_name }}]