Previously, one of the test route has the same address in destination
and gateway. Even it is a test case, that's super spurious. Let's use a
different address.
Strictly speaking, this breaks the backward compatibility, but I guess
in most cases people already sets Scope=link for such routes.
This behavior matches with how 'ip route' command adds such route by
default.
Prompted by https://twitter.com/jplitza/status/1480500562391179270.
Those are all consumed by our parser, so they all support comments.
I was considering whether they should have a license header at all,
but in the end I decided to add it because those files are often created
by copying parts of real unit files. And if the real ones have a license,
then those might as well. It's easier to add it than to make an exception.