Optimise npm install in squash for speed & logs visibility (#6158)

* Optimise npm install in squash for speed & logs

- `--no-optional` prevents installing dependencies that shouldn’t be needed for a one-off build
- `--no-audit` prevents running the `npm audit`
- `--progress=false`

* Add additional --no-fund flag to npm install

* Add "CI=true" environment variable to Squash builds for Node tooling

* Move CI=true to commands that need it

* Remove options that did not work

.squash.yml

@@ -8,7 +8,7 @@ deployments:
       - pip install setuptools pip --upgrade --force-reinstall
       - cd /code
     post_build_steps:  
-      - npm install --no-save
+      - npm install --no-save --no-audit --progress=false
       - npm run dist
       - pip install /code
       - mkdir /myproject