ERP5: prevent zope to start as long as the list of NEO master nodes is unknown

stack/erp5/buildout.cfg

@@ -288,7 +288,7 @@ md5sum = 9670cf63099e2c520017a23defff51a4
 [template-zope]
 <= download-base
 filename = instance-zope.cfg.in
-md5sum = 35f05cb0f8c8dc9c52bc02984bde49f5
+md5sum = 74f2fbd7d653b0e6cfe29efcd1042ace
 link-binary =
   ${aspell:location}/bin/aspell
   ${dmtx-utils:location}/bin/dmtxwrite

stack/erp5/instance-zope.cfg.in

@@ -254,6 +254,7 @@ node-id = {{ dumps(node_id_base ~ '-' ~ index) }}
 {%       do zodb['storage-dict'].__setitem__('name', slapparameter_dict['neo-cluster']) -%}
 {%       do zodb['storage-dict'].__setitem__('master_nodes', slapparameter_dict['neo-masters']) -%}
 {%     endif -%}
+{{     assert(zodb['storage-dict']['master_nodes'], db_name) }}
 {%   endif -%}
 {% endfor -%}
 import-list = {{ dumps(list(import_set)) }}