changed the gitlab ci to handle npm test

.gitlab-ci.yml

@@ -11,7 +11,7 @@ build:
     - mongo:latest
   script:
     - apk add --update nodejs=8.14.0-r0 nodejs-npm=8.14.0-r0
-    - npm install mocha -g
+    - npm install --global mocha
     - mocha --exit
     - git submodule init
     - git submodule update