[Frontend] Document and fix recommended npm daily practices

[Bobgy]

Summary:

• Use npm ci to
  • Install exact dependencies as before. @eterna2 pointed this out.
  • Keep node_modules up-to-date when someone else has installed a module.
• Commit package-lock.json and package.json when you installed/deleted packages.
• Use npm install --save (or npm i -S for short) for dependencies (dependency needed at runtime).
• Use npm install --save-dev (or npm i -D for short) for dev dependencies (dependency only used a develop time tool).
• Use npm uninstall [package] (or npm rm [package] for short) for removing any type of dependencies.
• Use npm audit/npm audit fix to deal with vulnerabilities.

Action items:

• Refine the above and add them to frontend contribution doc [Frontend] Update contribution doc with start proxy instructions and npm daily practices #3142.
• CI and dockerfile should use npm ci for package installation too in order for keeping the same package version as it was tested. (This can be a separate PR)
  Usages:
  • https://github.com/kubeflow/pipelines/blob/master/frontend/package.json#L53
  • https://github.com/kubeflow/pipelines/blob/master/frontend/Dockerfile#L19
  • https://github.com/kubeflow/pipelines/blob/master/test/frontend-integration-test/run_test.sh#L56
    Changes included in [UIServer] Add DISABLE_GKE_METADATA env flag to skip metadata retrieval. #3118

[Bobgy]

/priority p0