Update GitLab CI to use npm 11 to match package.json engines requirement

- Add npm install -g npm@11 after Node.js 22 installation
- Ensures CI environment meets npm 11+ requirement for engine-strict enforcement

Author: Taniya Mathur

.gitlab-ci.yml

@@ -45,6 +45,7 @@ developer_tests:
     # Install Node.js and npm for basedpyright
     - curl -fsSL https://deb.nodesource.com/setup_22.x | bash -
     - apt-get install -y nodejs
+    - npm install -g npm@11
     - npm install -g basedpyright
     - uv pip install ruff
     # Install dependencies needed by publish.py for test imports