s3tests: revert useless portion of 1c50db6a4630d07e72144dafd985c397f8a42dc5

Perhaps it was attempting to debug something, but it shouldn't have been committed.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
fix some errors found by pyflakes

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>