Bump tox from 3.3.0 to 3.4.0
Bump tox from 3.3.0 to 3.4.0

Bumps [tox](https://github.com/tox-dev/tox) from 3.3.0 to 3.4.0.
- [Release notes](https://github.com/tox-dev/tox/releases)
- [Changelog](https://github.com/tox-dev/tox/blob/master/CHANGELOG.rst)
- [Commits](https://github.com/tox-dev/tox/compare/3.3.0...3.4.0)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
marshmallow-code/apispec,marshmallow-code/smore