check_hobos: fix attribute_mapping if it contains None (#8923)

wcs/ctl/check_hobos.py

@@ -149,7 +149,7 @@ class CmdCheckHobos(Command):
 
         # add mapping for SAML provisioning
         for idp in pub.cfg.get('idp', {}).values():
-            if not 'attribute-mapping' in idp:
+            if not idp.get('attribute-mapping'):
                 idp['attribute-mapping'] = {}
             for field in profile.get('fields', []):
                 attribute_name = field['name']