[FlightRPC][C++][Python] Header-based auth in servers

Add support for a middleware that executes header-based authorization to C++ and Python servers.

The design should be such that a Flight server can validate incoming headers then generate a peer identity and write outgoing headers in response to the request.

Provide an implementation using Basic authentication.

**Reporter**: [James Duong](https://issues.apache.org/jira/browse/ARROW-10488) / @jduo

_{**Note**: *This issue was originally created as [ARROW-10488](https://issues.apache.org/jira/browse/ARROW-10488). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}

未指定任何文件或测试。首先定位 C++ 和 Python Flight 服务器中间件的入口点，然后跟踪传入和传出标头以及对端身份的处理方式。完成的标准是两个服务器都支持标头验证、对端身份生成、响应标头以及 Basic authentication 实现。

由索引模型根据 Issue 内容生成。