Python: Workflow orchestration API review

[TaoChenOSU]

Issue to track API review for Workflow orchestrations. This includes API names and parameters, duplicated APIs, public class names, etc.

• Concurrent
• Sequential
• Group Chat
• Magentic
• Handoff

[moonbox3]

This is going to take place as part of the larger workflows API review. Do we need this one-off issue? @markwallace-microsoft was going to create an epic to track the overall effort.