error fetching GPG key with version 2.1.4

[michaelw]

Error: Evaluation Error: Error while evaluating a Resource Statement, Apt::Source[repo_saltstack_com_major]: parameter 'keyring' expects a Stdlib::Absolutepath = Variant[Stdlib::Windowspath = Pattern[/\A(([a-zA-Z]:[\\\/])|([\\\/][\\\/][^\\\/]+[\\\/][^\\\/]+)|([\\\/][\\\/]\?[\\\/][^\\\/]+)).*\z/], Stdlib::Unixpath = Pattern[/\A\/([^\n\/\0]+\/*)*\z/]] value, got Struct (file: /etc/puppetlabs/code/environments/production/modules/salt/manifests/repo.pp, line: 44) on node ...

APT module version:

mod 'puppetlabs/apt', '9.1.0'

It seems the apt::source::keyring parameter does not allow URLs?