docs: updates multi-lang-support image (#8545)

Author: An-DJ

README.md

@@ -151,7 +151,7 @@ A/B testing, canary release, blue-green deployment, limit rate, defense against
 
 - **Multi-Language support**
   - Apache APISIX is a multi-language gateway for plugin development and provides support via `RPC` and `Wasm`.
-  ![Multi Language Support into Apache APISIX](docs/assets/images/apisix-multi-lang-support.png)
+  ![Multi Language Support into Apache APISIX](docs/assets/images/external-plugin.png)
   - The RPC way, is the current way. Developers can choose the language according to their needs and after starting an independent process with the RPC, it exchanges data with APISIX through local RPC communication. Till this moment, APISIX has support for [Java](https://github.com/apache/apisix-java-plugin-runner), [Golang](https://github.com/apache/apisix-go-plugin-runner), [Python](https://github.com/apache/apisix-python-plugin-runner) and Node.js.
   - The Wasm or WebAssembly, is an experimental way. APISIX can load and run Wasm bytecode via APISIX [wasm plugin](https://github.com/apache/apisix/blob/master/docs/en/latest/wasm.md) written with the [Proxy Wasm SDK](https://github.com/proxy-wasm/spec#sdks). Developers only need to write the code according to the SDK and then compile it into a Wasm bytecode that runs on Wasm VM with APISIX.
 

docs/zh/latest/README.md

@@ -154,7 +154,7 @@ A/B 测试、金丝雀发布（灰度发布）、蓝绿部署、限流限速、
 
 - **多语言支持**
 - Apache APISIX 是一个通过 `RPC` 和 `Wasm` 支持不同语言来进行插件开发的网关。
-  ![Multi Language Support into Apache APISIX](../../../docs/assets/images/apisix-multi-lang-support.png)
+  ![Multi Language Support into Apache APISIX](../../../docs/assets/images/external-plugin.png)
     - RPC 是当前采用的开发方式。开发者可以使用他们需要的语言来进行 RPC 服务的开发，该 RPC 通过本地通讯来跟 APISIX 进行数据交换。到目前为止，APISIX 已支持[Java](https://github.com/apache/apisix-java-plugin-runner), [Golang](https://github.com/apache/apisix-go-plugin-runner), [Python](https://github.com/apache/apisix-python-plugin-runner) 和 Node.js。
     - Wasm 或 WebAssembly 是实验性的开发方式。 APISIX 能加载运行使用[Proxy Wasm SDK](https://github.com/proxy-wasm/spec#sdks)编译的 Wasm 字节码。开发者仅需要使用该 SDK 编写代码，然后编译成 Wasm 字节码，即可运行在 APISIX 中的 Wasm 虚拟机中。