Create ci user keychain fails due to permissions issue

[navops29]

I am trying to use the ansible-role-osx-ci to set up a Mojave machine on Macstadium and I get the following error:

TASK [macstadium.osx_ci : Create ci user keychain] ***********************************************************************************************************************************************************************************************************
fatal: [<ip-redacted>]: FAILED! => {
    "msg": "Failed to set permissions on the temporary files Ansible needs to create when becoming an unprivileged user (rc: 1, err: chown: /var/tmp/ansible-tmp-1614801194.6299698-24857-84616697763498/: Operation not permitted\nchown: /var/tmp/ansible-tmp-1614801194.6299698-24857-84616697763498/AnsiballZ_keychain.py: Operation not permitted\n}). For information on working around this, see https://docs.ansible.com/ansible/become.html#becoming-an-unprivileged-user"
}

The ci-user gets created successfully, but the next step to create the user keychain fails (The link present in the error message does not work).

Any help is appreciated. Thanks!