Multiple HttpClient instances created for Actor and Workflow clients causing unexpected cancellations

[nelson-parente]

The dotnet SDK appears to create more than one HttpClient instance for the actor and workflow clients. This leads to one client cancelling requests made by the other.

The behavior has been reproduced internally. There is an extra HttpClient instance being created somewhere in the SDK, and this results in cross cancellations during workflow execution.

This needs investigation and prioritization because it affects both actors and workflows.

[WhitWaldo]

@nelson-parente Do you happen to have a repro I can look at?