ServiceComb支持通过代码配置开启TLS，提升配置灵活性

通过阅读文档[使用TLS通信](https://servicecomb.apache.org/references/java-chassis/zh_CN/security/tls.html)了解service comb可以支持TLS通信，并且可以通过microservice.yaml对依赖的证书等信息进行配置。
这种方式对于证书信息需要从第三方软件获取，比如从apollo、consul等配置中心获取的场景支持不够灵活。service comb团队是否考虑扩展证书配置机制以支持在运行时通过code进行配置，类似Spring Boot中的WebServerFactoryCustomizer。

Start with the linked “使用TLS通信” documentation and trace how certificate settings are currently supplied through microservice.yaml. Compare that flow with the requested runtime, code-based configuration and the Spring Boot WebServerFactoryCustomizer model. Done means the supported configuration mechanism and its scope are clearly defined for certificates obtained from external configuration centers.

Written by the indexing model from the issue text.