Apache APISIX: Add plugin for Mutual TLS Authentication

Apache APISIX is a dynamic, real-time, high-performance API gateway.

It provides rich traffic management features such as load balancing, dynamic upstream, canary release, circuit breaking, authentication, observability, and more.

Page: https://apisix.apache.org/

Github: https://github.com/apache/apisix

Background:

Apache APISIX supports Mutual TLS, but we can only configure it on the SSL object. We want to create a plugin to support mTLS. So that we can use it on the route or service.

Task:

• Design the plugin of `Mutual TLS Authentication`
• Develop the plugin.