Bumps [serde_yaml](https://github.com/dtolnay/serde-yaml) from 0.8.8 to 0.8.9. - [Release notes](https://github.com/dtolnay/serde-yaml/releases) - [Commits](https://github.com/dtolnay/serde-yaml/compare/0.8.8...0.8.9) Signed-off-by: dependabot[bot] <support@dependabot.com>