Capsule Upgrade Playbook is failing with connection error.

Issue

• Capsule Upgrade Playbook is failing with the below error:

    fatal: [capsule.example.com]: UNREACHABLE! => {"changed": false, "msg": "Failed to connect to the host via ssh: 
    Failed to add the host to the list of known hosts (/usr/share/foreman-proxy/.ssh/known_hosts).\r\nAuthorized uses only. All 
    activity may be monitored and reported.\nConnection to 10.20.30.40 closed by remote host.\r\nConnection to 10.20.30.40 
    closed.", "unreachable": true}