YAML extra deps cause the sandbox creation to fail
TASK [Install YAML::Syck, CGI::Session::Serialize::YAML, needed for Koha <= 21.05] ***
fatal: [localhost -> koha-serialstat]: FAILED! => {"changed": false, "module_stderr": "", "module_stdout": "", "msg": "MODULE FAILURE\nSee stdout/stderr for the exact error", "rc": 137}