Bug#1095392: smart-open FTBFS: tests hang

[Rebecca N. Palmer]

This also hangs in debci, and began doing so between 2025-01-29 and 
2025-02-01 (in unstable):
https://ci.debian.net/packages/s/smart-open/unstable/amd64/
Looking at what changed version between those, the obvious guess is 
python3-botocore 1.35 -> 1.36 (which did not trigger an autopkgtest 
because the *direct* dependency is python3-boto3).