Bump s3transfer from 0.3.3 to 0.3.4
Bump s3transfer from 0.3.3 to 0.3.4

Bumps [s3transfer](https://github.com/boto/s3transfer) from 0.3.3 to 0.3.4.
- [Release notes](https://github.com/boto/s3transfer/releases)
- [Changelog](https://github.com/boto/s3transfer/blob/develop/CHANGELOG.rst)
- [Commits](https://github.com/boto/s3transfer/compare/0.3.3...0.3.4)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
mozilla-services/kinto-dist,mozilla-services/kinto-dist