Update architecture graph. (#6823)

README.md

@@ -4,7 +4,7 @@ Apache SkyWalking
 <img src="http://skywalking.apache.org/assets/logo.svg" alt="Sky Walking logo" height="90px" align="right" />
 
 **SkyWalking**: an APM(application performance monitor) system, especially designed for
-microservices, cloud native and container-based (Docker, Kubernetes, Mesos) architectures.
+microservices, cloud native and container-based architectures.
 
 [![GitHub stars](https://img.shields.io/github/stars/apache/skywalking.svg?style=for-the-badge&label=Stars&logo=github)](https://github.com/apache/skywalking)
 [![Twitter Follow](https://img.shields.io/twitter/follow/asfskywalking.svg?style=for-the-badge&label=Follow&logo=twitter)](https://twitter.com/AsfSkyWalking)
@@ -31,7 +31,7 @@ The core features are following.
 - Infrastructure(VM, network, disk etc.) monitoring
 - Collaboration across metrics, traces, and logs
 
-<img src="http://skywalking.apache.org/assets/frame-v8.jpg?u=20201105"/>
+<img src="https://skywalking.apache.org/images/SkyWalking_Architecture_20210424.png"/>
 
 SkyWalking supports to collect telemetry (metrics, traces, and logs) data from multiple sources
 and multiple formats,