Fix docker build (#2348)

* .eslintrc.json is required to build using react-scripts

* Remove the extra "deps" step

This step can be done as part of the build (faster and more reliable).

* Add a GitHub Actions to build the Docker image

Make sure that "docker build" is working on every pull request before landing on master.

* Update package-lock.json

* Add .prettierrc in the Docker image to avoid warnings in the build step

* Revert "Update package-lock.json"

This reverts commit 7ef2eaadfae610771987bc8155670b895c139e7b.

* Make sure that the 'node_modules' layer can be cached

if package and package-lock.json didn't changed

Dockerfile

@@ -1,25 +1,14 @@
-FROM node:14-alpine AS deps
-
-ARG REACT_APP_INCLUDE_GTAG=false
-
-RUN mkdir /opt/node_app && chown node:node /opt/node_app
-WORKDIR /opt/node_app
-
-USER node
-
-COPY package.json package-lock.json ./
-RUN npm install --no-optional && npm cache clean --force
-ENV PATH /opt/node_app/node_modules/.bin:$PATH
-
-WORKDIR /opt/node_app
-COPY . .
-
 FROM node:14-alpine AS build
 
+WORKDIR /opt/node_app
+
+COPY package.json package-lock.json ./
+RUN npm i --no-optional
+
+ARG REACT_APP_INCLUDE_GTAG=false
 ARG NODE_ENV=production
 
-WORKDIR /opt/node_app
-COPY --from=deps /opt/node_app .
+COPY . .
 RUN npm run build:app:docker
 
 FROM nginx:1.17-alpine