Running the taskotron-trigger's unittests requires that correct /var/lib/taskotron-trigger/critpath_whitelist file is present on the disk. Mock the utils.parse_yaml_from_file method so it just returns reasonable data, instead of parsing file from disk.
/var/lib/taskotron-trigger/critpath_whitelist
utils.parse_yaml_from_file
This ticket had assigned some Differential requests: D864
Yeah, just noticed that today as well. Working on it.