update base image

.gitlab-ci.yml

 # In case something goes horribly wrong, you can fall back to `image: ruby:latest`
-image: git-r3lab.uni.lu:4567/r3/docker/jekyll-lcsb:1.0
+image: git-r3lab.uni.lu:4567/r3/docker/jekyll-lcsb:1.1
 
 stages:
   - build
@@ -10,7 +10,7 @@ stages:
 build the website:
   stage: build
   before_script:
-  - gem install bundler -v2.0.2
+  - gem install bundler:2.0.2
   - bundle install && bundle update jekyll-theme-lcsb-default && bundle update jekyll-theme-lcsb-frozen-components
   script:
   - bundle exec jekyll build -d build --config "_config.yml,_config_staticpages.yml"
@@ -65,7 +65,7 @@ Create the backup:
   artifacts:
     expire_in: 2 weeks
     paths:
-    - backups    
+    - backups
   script:
     - ssh -p $SSHPORT $SSHCONNECT "mkdir -p ~/web ~/backups/; cd /var/www/sites/r3lab.uni.lu; tar -zcvf ~/backups/backup_$(date +'%Y_%m_%d').tar.gz *"
     - ssh -p $SSHPORT $SSHCONNECT "cd ~/backups/; ls -tr | head -n -3 | xargs --no-run-if-empty rm "