[conda] Re-run the build during test

conda/meta.yaml

@@ -63,7 +63,7 @@ test:
     - beat editor serve --help
     - nosetests --with-coverage --cover-package={{ name }} -sv {{ name }}
     - export CHROMIUM_BIN=chromium-browser
-    - if [ -n "${BEAT_BROWSER_TESTS}" ]; then cd js; npm install; npm test; cd -; fi
+    - if [ -n "${BEAT_BROWSER_TESTS}" ]; then cd js; npm install; npm run build; npm test; cd -; fi
     - unset CHROMIUM_BIN
     - sphinx-build -aEW ${PREFIX}/share/doc/{{ name }}/doc sphinx
     - if [ -n "${CI_PROJECT_DIR}" ]; then mv sphinx "${CI_PROJECT_DIR}/"; fi