changed: oidc username_claim default to

Signed-off-by: Danny Eiselt <eiselt@b1-systems.de>

providers/openstack/scs/cluster-class/templates/cluster-class.yaml

@@ -277,7 +277,7 @@ empty path"
            username_claim:
              type: string
              example: "preferred_username"
-             default: "sub"
+             default: "preferred_username"
              description: "JWT claim to use as the user name. By default sub,
 which is expected to be a unique identifier of the end user. Admins can choose
 other claims, such as email or name, depending on their provider. However,