Bump altair from 3.2.0 to 3.3.0 (#337)
Bump altair from 3.2.0 to 3.3.0 (#337)

Bumps [altair](https://github.com/altair-viz/altair) from 3.2.0 to 3.3.0.
- [Release notes](https://github.com/altair-viz/altair/releases)
- [Changelog](https://github.com/altair-viz/altair/blob/master/CHANGES.md)
- [Commits](https://github.com/altair-viz/altair/compare/v3.2.0...v3.3.0)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
larq/larq