Update async requirement from ^0.9.0 to ^2.6.3
Update async requirement from ^0.9.0 to ^2.6.3

Updates the requirements on [async](https://github.com/caolan/async) to permit the latest version.
- [Release notes](https://github.com/caolan/async/releases)
- [Changelog](https://github.com/caolan/async/blob/v2.6.3/CHANGELOG.md)
- [Commits](https://github.com/caolan/async/compare/0.9.0...v2.6.3)

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