Added dockerfile for user-service

backend-services/user-service/Dockerfile

+FROM node:latest as base
+
+# Create app directory
+WORKDIR /user-service/app
+
+COPY package*.json ./
+RUN  npm install
+
+# Bundle app source
+COPY . .
+
+EXPOSE 9000
+
+CMD [ "npm", "run", "start" ]
\ No newline at end of file