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 7ef2eaadfa.

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

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

.dockerignore

@@ -2,6 +2,8 @@
 !public/
 !src/
 !.npmrc
+!.eslintrc.json
+!.prettierrc
 !package-lock.json
 !package.json
 !tsconfig.json