Consolidate CDC env file.

[keyurva]

• Consolidates CDC env vars into a single file (env.list).

• See go/cdc-env-file-consolidation for more details.

• As part of the consolidation sqlite_env.list and cloudsql_env.list need to be removed.

  • We'll remove them from the code once @kmoscoe has removed their mention from the docs.

• Dockerfile changes:

  • lancedb deps were moved to a different requirements file a few weeks ago. Adapting Dockerfile to that move.
  • Uses npm ci vs npm install for faster builds. See this thread for more details.

• The Dockerfile changes are not related to env consolidation so I can do it in a separate PR if needed. LMK.

• Built docker image (gcr.io/datcom-ci/datacommons-website-compose:keyurs-test) with these changes and verified in the cloud here.