feat: server Dockerfile - added USER instruction not to run under the root user

backend/Dockerfile

 #---------- DEVELOPMENT ----------
 FROM node:16-alpine AS development
 
+# we do not want to run under the root user
+USER node
+
 # install node_modules outside app root in container so local development won't run into a problem of bind-mounting over it with local source code
 WORKDIR /usr/src
 
-COPY ["package.json", "package-lock.json", "./"]
+COPY --chown=node:node ["package.json", "package-lock.json", "./"]
 RUN npm install
 # ensures that exactly these executables (from the node_modules folder) are used instead of any other executables which might also be installed on the system inside the Docker image
 ENV PATH=/usr/src/node_modules/.bin:$PATH
 
 WORKDIR /usr/src/app
 
-COPY prisma/schema.prisma ./prisma/
+COPY --chown=node:node prisma/schema.prisma ./prisma/
 RUN npx prisma generate
 
-COPY . .
+COPY --chown=node:node . .
 
 CMD ["npm", "run", "start:dev"]
 
@@ -22,13 +25,16 @@ CMD ["npm", "run", "start:dev"]
 #---------- PRODUCTION ----------
 FROM node:16-alpine AS production
 
+# we do not want to run under the root user
+USER node
+
 ARG NODE_ENV=production
 ENV NODE_ENV=${NODE_ENV}
 
 WORKDIR /usr/src
 
-COPY --from=development /usr/src/package.json ./
-COPY --from=development /usr/src/package-lock.json ./
+COPY --chown=node:node --from=development /usr/src/package.json ./
+COPY --chown=node:node --from=development /usr/src/package-lock.json ./
 # install only 'dependencies' and not 'devDependencies'
 RUN npm install --omit=dev
 # ensures that exactly these executables (from the node_modules folder) are used instead of any other executables which might also be installed on the system inside the Docker image
@@ -36,9 +42,9 @@ ENV PATH=/usr/src/node_modules/.bin:$PATH
 
 WORKDIR /usr/src/app
 
-COPY prisma/schema.prisma ./prisma/
+COPY --chown=node:node prisma/schema.prisma ./prisma/
 RUN npx prisma generate
 
-COPY --from=development /usr/src/app/dist ./dist
+COPY --chown=node:node --from=development /usr/src/app/dist ./dist
 
 CMD ["npm", "run", "start:prod"]