python3-sphinx: upgrade 6.0.0 -> 6.1.3

License-Update: Update copyright years

https://www.sphinx-doc.org/en/master/changes.html#release-6-1-3-released-jan-10-2023
https://www.sphinx-doc.org/en/master/changes.html#release-6-1-2-released-jan-07-2023
https://www.sphinx-doc.org/en/master/changes.html#release-6-1-1-released-jan-05-2023
https://www.sphinx-doc.org/en/master/changes.html#release-6-1-0-released-jan-05-2023
https://www.sphinx-doc.org/en/master/changes.html#release-6-0-1-released-jan-05-2023



Signed-off-by: Tim Orling <tim.orling@konsulko.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>