Update README

Author: Charoite Lee

README.md

@@ -10,10 +10,10 @@
 
 ## How this layer is built?
 
-The Lambda Layer is built from source of node-canvas npm package on EC2 instance, with following native dependencies installed. Please check ``` build-layer.sh ``` for details.
+The Lambda Layer is built from source of node-canvas npm package on [amazonlinux](https://hub.docker.com/_/amazonlinux) dev container instance, with following native dependencies installed. Please check ``` build-layer.sh ``` for details.
 
 ```bash
-gcc-c++ cairo-devel pango-devel libjpeg-turbo-devel giflib-devel librsvg2-devel pango-devel bzip2-devel
+gcc-c++ cairo-devel pango-devel libjpeg-turbo-devel giflib-devel librsvg2-devel pango-devel bzip2-devel jq python3
 ```
 
 Since AWS Lambda is a secure and isolated runtime and execution environment, this layer aims to target AWS Lambda compatible build. As there are canvas libraries and frameworks relying on node-canvas running on Node.js runtime, this layer also tries to include and support these libraries and frameworks.