[Feature Request] Create sample for calling Python Client from a sync method

Is your feature request related to a problem? Please describe.

There are many Temporal users that have existing Python code bases that are only sync, and for these users learning how to invoke the Temporal Client is toil, as they may not be fully versed in asyncio and the event loop. Having a sample that provides a snippet on how to use the Temporal Client from an existing sync method would be very helpful for these folks as part of the getting started experience.

Describe the solution you'd like

I'd like a hello world style sample that creates a client and then invokes client.start_workflow or client.execute_workflow from within a synchronous method

Additional context

まず、リポジトリに既存する hello-world サンプルと Python Client の使用パターンを確認してください。issue では特定のファイルやテストは指定されていません。同期メソッドから client.start_workflow または client.execute_workflow を呼び出すサンプルを追加し、そのサンプルが getting-started エクスペリエンスの一部として実行されることを確認してください。