nixos/tests/openssh: use dashes for hostnames

Otherwise the tests will fail with `networking.useNetworkd = true;`
because `systemd-resolved` ignores invalid hostnames in `/etc/hosts`
(which is where all hosts from the `nodes`-attribute set end up) and
subsequently e.g. `ssh server_lazy` will fail because the name cannot be
resolved.

In d6e84a4574a200de63e8fe86ef8574b507fd366e the test-framework was
changed to replace all dashes with underscores of hostnames in the
python code to have readable hostnames that are valid. I.e.

    nodes.foo-bar = {}

represents a host with a valid hostname and it can be referenced in the
`testScript` with `foo_bar`.

Applying this here fixes the test for both scripted networking and
networkd.

0 files changed, 0 insertions, 0 deletions