Adjust `npm install` in travis / docker setup

.travis.yml

@@ -37,6 +37,7 @@ matrix:
   - name: "E2E tests"
     env: RUN_E2E=1
     script:
+      - npm install
       - npm run build
       - docker-compose up -d
       - travis_retry bash tests/bin/run-e2e-CI.sh

tests/bin/run-e2e-CI.sh

@@ -1,5 +1,4 @@
 #!/usr/bin/env bash
-npm install;
 echo "Waiting for 5 minutes for the Docker container to start...";
 sleep 300;
 npm run test:e2e;