[#1178] Simplify "if" expression, removing redundancy

ckan/controllers/group.py

@@ -614,7 +614,7 @@ def member_new(self, id):
                 data_dict['id'] = id
 
                 email = data_dict.get('email')
-                if email and email != '':
+                if email:
                     user_data_dict = {
                         'email': email,
                         'group_id': data_dict['id'],