restore build and test jobs

.gitlab-ci.yml

 stages:
   - github-sync
+  - build
+  - test
   - releases
   - releases-page
 push_to_github:
@@ -20,6 +22,27 @@ push_to_github:
         - mv packed-refs-new packed-refs
         - bash -c "git push --force --mirror github 2>&1 | grep -v duniter-gitlab; echo $?"
         
+build:
+  stage: build
+  tags:
+    - redshift
+  before_script:
+    - export NVM_DIR="$HOME/.nvm"
+    - . "$NVM_DIR/nvm.sh"
+  script:
+    - yarn
+
+test:
+  stage: test
+  tags:
+    - redshift
+  before_script:
+    - export NVM_DIR="$HOME/.nvm"
+    - . "$NVM_DIR/nvm.sh"
+  script:
+    - yarn
+    - yarn test
+
 releases:test:
   stage: releases
   image: duniter/release-builder:v1.0.1