[Workflows] Missing `SendEvent` feature

[olitomlinson]

The goal is that all Workflows Languages have the ability to raise an Event directly from one Workflow to another Workflow via a SendEvent method on the Workflow Context. The JS SDK is missing this feature.

We aim to strive for feature parity across language SDKs so this should be implemented.

Dotnet Example

[WhitWaldo]

@olitomlinson Unfortunately, it doesn't appear that the SendEvent method is implemented in either our fork of durabletask-js or Microsoft's version. I'll see if I can't see what this does in the .NET version and port it over, but that definitely makes this a bigger ask than just referencing a skipped internal method.