[Design-team] Updated f23-backgrounds ready for testing

[Luya Tshimbalanga]

f23-backgrounds packages are ready for testing [1] ahead of schedule as
I find out a few spins need to update before the freeze which happened
to be on October 13. .
Default wallpaper is updated to the latest version and extra backgrounds
are included.
 Tomorrow is Thanksgiving in Canada so I may be not available online.

Reference
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[1] https://bodhi.fedoraproject.org/updates/f23-backgrounds-23.1.0-1.fc23