Merge branch '3-upgrade-dockerfile-so-that-it-could-benefit-from-cache' into 'master'

feat: upgrade Dockerfile

Closes #3

See merge request !7
1 job for 1.3 in 5 minutes and 20 seconds
Status Job ID Name Coverage
  Build
failed #134263
privileged
build and publish the image

00:05:20

 
Name Stage Failure
failed
build and publish the image Build
Bundle updated!
Removing intermediate container 0cef750b559d
---> b82f58c25522
Successfully built b82f58c25522
$ docker build -t $CI_REGISTRY_IMAGE:$(CI_COMMIT_TAG) .
/bin/sh: eval: line 97: CI_COMMIT_TAG: not found
invalid argument "git-r3lab.uni.lu:4567/r3/docker/jekyll-lcsb:" for "-t, --tag" flag: invalid reference format
See 'docker build --help'.
ERROR: Job failed: exit code 125