Fix keyword argument repeated in setup.py

[giansegato]

setup.py mention install_requires twice (likely a typo).

root@56e1be9f59d2:/bitsandbytes# python3 setup.py install
  File "setup.py", line 32
    install_requires=['torch', 'numpy', 'scipy'],
    ^
SyntaxError: keyword argument repeated

This removes the first mention (already covered by the latter one).

[Titus-von-Koeller]

Hey! Thanks for raising this. Seems someone else submitted the same fix a few hours later. Going down the list from the newest first, I saw yours only after already merging the other. Sorry!

Thanks anyways and hope to be able to merge your next contribution soon. Very happy to see so much activate participation here! 🙌🏻