maint: removed test which is outdated
maint: removed test which is outdated

It is now allowed to do Hk([] != 0, dtype=float) which is
automatically up-casted to the same complex data-type.

Signed-off-by: Nick Papior <81a73bca3d342ffee33d7cf845fdbf77b6553831@gmail.com>

zerothi/sisl,zerothi/sisl