[docs] Write HTTP in uppercase (issue 26553)

[vadmium+py at gmail.com]

https://bugs.python.org/review/26553/diff/16771/Doc/library/urllib.request.rst
File Doc/library/urllib.request.rst (right):

https://bugs.python.org/review/26553/diff/16771/Doc/library/urllib.request.rst#newcode74
Doc/library/urllib.request.rst:74: For HTTP and HTTPS urls, this
function returns a
HTTPS URLs

https://bugs.python.org/review/26553/