Test Server hanging or reporting completed on start update requests

[Sushisource]

While testing update for Python SDK against the Test server, the server was either hanging (when downloaded from the CDN) or reporting the workflow was complete when it wasn't/shouldn't be (running locally from this repo) after one successful update call.

Not much to go on here since there are no logs really and I haven't had time to dig in with a debugger yet. Opening this so I have an issue to reference in skipped tests in Python.

[cretz]

This same issue is happening in .NET: temporalio/sdk-dotnet#179. Updates are accepted but then nothing happens. I too have not debugged this.