Bump mailchimp3 from 3.0.7 to 3.0.9

Bumps [mailchimp3](https://github.com/charlesthk/python-mailchimp) from 3.0.7 to 3.0.9.
- [Release notes](https://github.com/charlesthk/python-mailchimp/releases)
- [Commits](https://github.com/charlesthk/python-mailchimp/commits

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>