statprof: ensure files with binary I/O are opened in binary mode These appear to have been existing bugs, so maybe this should go on stable. OTOH, PyCharm is flagging 8 other things in this file, claiming symbols and/or imports don't exist. I haven't dug into that, but suspect that this module isn't used much, based on the bugs fixed here and no previous complaints. These were previously hidden by the `pycompat.open()` import, because that is typed as returning `Any` instead of `BinaryIO`. (I didn't look up the reason for that, but do recall there was one.)