Issue #14099: ZipFile.open() no longer reopen the underlying file. Objects

returned by ZipFile.open() can now operate independently of the ZipFile even
if the ZipFile was created by passing in a file-like object as the first
argument to the constructor.

diff --cc Lib/test/test_zipfile.py
Simple merge

diff --cc Lib/zipfile.py
Simple merge

diff --cc Misc/NEWS
Simple merge