fleetd no longer has default etcd endpoints

[mischief]

since approximately 30f9f1f, fleetd no longer has default etcd endpoints, resulting in fleetd exiting if no configuration is specified.

Jul 09 22:03:22 localhost systemd[1]: Started fleet daemon.
Jul 09 22:03:22 localhost systemd[1]: Starting fleet daemon...
Jul 09 22:03:22 localhost fleetd[566]: INFO fleetd.go:64: Starting fleetd version 0.11.0
Jul 09 22:03:22 localhost fleetd[566]: INFO fleetd.go:168: No provided or default config file found - proceeding without
Jul 09 22:03:22 localhost fleetd[566]: FATAL fleetd.go:90: Failed creating Server: client: no endpoints available
Jul 09 22:03:22 localhost systemd[1]: fleet.service: Main process exited, code=exited, status=1/FAILURE
Jul 09 22:03:22 localhost systemd[1]: fleet.service: Unit entered failed state.
Jul 09 22:03:22 localhost systemd[1]: fleet.service: Failed with result 'exit-code'.