[chapter 7] update main readme

Signed-off-by: danbugs <[email protected]>

Author: danbugs

README.md

@@ -15,7 +15,7 @@ The book is still under development, so this repository will be updated as I pro
 - Part 2: WebAssembly for developers
     - [x] Chapter 6 (Creating Production-Grade Wasm Applications)
 - Part 3: Wasm on the Cloud and the Edge
-    - [ ] Chapter 7 (Introducing Wasm Containers with Docker)
+    - [x] Chapter 7 (Distributing and deploying Wasm)
     - [ ] Chapter 8 (Scalability for Wasm with Kubernetes)
     - [ ] Chapter 9 (Wasm for Edge Devices and IoT)