Fixing the build job

Not sure why, but before_script seems to always succeed even if a step fails.

.gitlab-ci.yml

@@ -51,6 +51,7 @@ compile:
   needs:
     - ["env"]
   script:
+    - mkdir -p build && cd build && cmake ../. -DCMAKE_INSTALL_PREFIX=/usr/local && make -j20 && make install  && cd ..
     - echo "Build successful."
 
 .views: