UPD: better nodejs installation

.gitlab-ci.yml

 before_script:
     ## dependencies
     
-    - curl -sL https://deb.nodesource.com/setup_11.x | bash -
-    - apt-get install -y nodejs python3-requests
+    - apt-get update -y
+    - test -e  /etc/apt/sources.list.d/nodesource.list || curl -s https://deb.nodesource.com/gpgkey/nodesource.gpg.key | apt-key add -
+    - test -e  /etc/apt/sources.list.d/nodesource.list || echo 'deb https://deb.nodesource.com/node_13.x stretch main' > /etc/apt/sources.list.d/nodesource.list
+    - 'which npm || (apt-get update -y && apt-get install -y nodejs)'
+    - apt-get install python3-requests
     - cd frontend/
     - cp netvs.config.js.example netvs.config.js
     - npm install
@@ -10,7 +13,7 @@ before_script:
 
     ## Deployment
 
-    - 'which ssh-agent || ( apt-get update -y && apt-get install openssh-client -y )'
+    - 'which ssh-agent || ( apt-get install openssh-client -y )'
     - eval $(ssh-agent -s)
     - echo "$SSH_PRIVATE_KEY" | tr -d '\r' | ssh-add -
     - mkdir -p ~/.ssh