Bump symfony/yaml from 4.2.9 to 4.3.0
Bump symfony/yaml from 4.2.9 to 4.3.0

Bumps [symfony/yaml](https://github.com/symfony/yaml) from 4.2.9 to 4.3.0.
- [Release notes](https://github.com/symfony/yaml/releases)
- [Changelog](https://github.com/symfony/yaml/blob/master/CHANGELOG.md)
- [Commits](https://github.com/symfony/yaml/compare/v4.2.9...v4.3.0)
linuxjuggler/database-backup