Fix missing peer dependency of vega-lite

Signed-off-by: Aravind V Nair <22199259+aravindvnair99@users.noreply.github.com>

Dockerfile

@@ -1,20 +1,16 @@
 FROM nikolaik/python-nodejs:python3.8-nodejs12
 
-# Install dependencies.
 ADD requirements.txt /requirements.txt
 ADD main.py /main.py
 ADD loc.py /loc.py
 ADD make_bar_graph.py /make_bar_graph.py
 ADD colors.json /colors.json
 ADD translation.json /translation.json
-RUN pip install -r requirements.txt
 
 ENV NPM_CONFIG_PREFIX=/home/node/.npm-global
 
+RUN pip install -r requirements.txt
 RUN npm -g config set user root
-
-RUN npm install -g vega@^5.19.1 
-
-RUN npm install -g vega-lite vega-cli canvas
+RUN npm i -g vega vega-lite vega-cli canvas
 
 ENTRYPOINT ["python", "/main.py"]