CI: Handle variant of unknown user error message seen on MacOS

tests/ansible/integration/become/sudo_nonexistent.yml

@@ -23,6 +23,7 @@
           # removed user/group error messages, as defence against CVE-2019-14287.
           - >-
             ('sudo: unknown user: slartibartfast' in out.module_stderr | default(out.msg))
+            or ('chown: slartibartfast: illegal user name' in out.module_stderr | default(out.msg))
             or (ansible_facts.os_family == 'RedHat' and ansible_facts.distribution_version == '6.10')
         fail_msg: out={{out}}
       when: