Added Mail channel package for Notification (#663)
* Added Mail channel package for Notification
* Apply cs-fix
* fix
* Added GenMarkdownMailCommand
* Apply cs-fix
* Added unit tests
* Fixed
* Update
* Apply fix
* [Dependency Injection] Update MailManager binding to use closure for dynamic resolution
* chore: Skip beta components in release script
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Co-authored-by: Deeka Wong <8337659+huangdijia@users.noreply.github.com>