We need to explicitly add the GPG signing key for the _dch_ repository
to the system trust store, otherwise, _dnf-automatic_ will fail, as it
cannot implicitly add new keys during an update.
*unifi1.pyrocufflink.blue* requires a proxy to access Yum repositories
on the Internet, so it has the `proxy` setting configured globally. The
proxy does NOT allow access to internal resources, however. The
internal repository is directly accessible by that machine, so it needs
to be configured thus.
The *dch* repository, hosted on *file0.pyrocufflink.blue* and managed by
the *repohost* Ansible role, is where I plan to host RPM packages for
internal use (e.g. *sshca-cli*, *dch-selinux*, etc.). The *dch-yum*
role configures Yum/dnf to use this repository. Roles that need to
install a package from here will list this role as a dependency.
