Comment 1 for bug 1951849

Ansible is known for really bad error reporting.
This is the offending line:

    regexp: "^127.0.1.1\\b.*\\s{{ ansible_facts.hostname }}\\b"

Seemingly, in your case ansible_facts are missing hostname.
As this is the first usage of ansible_facts in this action, I would check if facts were collected and bingo - they were not (based on your log):

    PLAY [Gather facts for all hosts]
    skipping: no hosts matched

You have an inventory parsing error above:

    [WARNING]: * Failed to parse /etc/kolla/multinode with yaml plugin...

It shall work when you fix it.