This addresses an issue with delegation to containers noticed
as a result of https://github.com/ansible/ansible/issues/72776
which causes the container host to be accessed by its hostname.
Where a separate deploy host is used, up to now this has not had
its hosts file modified. This patch applies the same /etc/hosts
entries to the deploy host which are used elsewhere.
Change-Id: I82b48ba5cfe6e533426e7098c455b729084b2d51