Install task skipped when ansible_pkg_mgr fact is unknown

[dorranh]

Hi, we recently encountered what appears to be a bug or unexpected behavior when using Datadog Agent role to provision a pinned version of Datadog Agent (specifically on Amazon Linux 2). In our case the ansible_pkgs_mgr fact evaluated to unknown for an unknown reason when running our playbook. This resulted in the role skipping the datadog-agent install task despite successfully updating the yum repository to point to the pinned version requested in the role variables. In the end the playbook run succeeded, but the newer version of Datadog Agent was not installed.

Is this expected behavior, and if so, would it be possible to add logic to fail fast in this case?