Minify Dockerfile and Update README

Dockerfile

@@ -1,7 +1,4 @@
-# This Dockerfile is friendly to users in Chinese Mainland :)
-# For users outside mainland China, feel free to modify or delete them :)
-
-# Use a base image with Python 3.9.17 slim version (Bullseye)
+# Use a base image with Python3.9 and Nodejs20 slim version
 FROM nikolaik/python-nodejs:python3.9-nodejs20-slim
 
 # Install Debian software needed by MetaGPT
@@ -9,21 +6,15 @@ RUN apt update &&\
     apt install -y git chromium fonts-ipafont-gothic fonts-wqy-zenhei fonts-thai-tlwg fonts-kacst fonts-freefont-ttf libxss1 --no-install-recommends &&\
     apt clean
 
-# Set the working directory to /app
-WORKDIR /app
-
 # Install Mermaid CLI globally
-ENV CHROME_BIN="/usr/bin/chromium"
-ENV AM_I_IN_A_DOCKER_CONTAINER Yes
-ADD puppeteer-config.json  /puppeteer-config.json
+ENV CHROME_BIN="/usr/bin/chromium" \
+    AM_I_IN_A_DOCKER_CONTAINER="true"
 RUN npm install -g @mermaid-js/mermaid-cli &&\
     npm cache clean --force
 
-# Copy src to container the MetaGPT repository
-COPY . /app/metagpt
-
 # Install Python dependencies and install MetaGPT
-RUN cd metagpt &&\
+COPY . /app/metagpt
+RUN cd /app/metagpt &&\
     mkdir workspace &&\
     pip install -r requirements.txt &&\
     pip cache purge &&\