Update README

[kylewu]

Please update README.

• In Local Deployment, AWS S3 Setup needs to be updated: s3 is run in docker compose: minio
• In Local Deployment, Mock API needs to be updated, because mock api is run in docker compose now.

We need to mention all dependencies, and they are all ready after running docker-compose up.

• In Running tests, please add "Prepare" in both "Running unit tests" and "Running integration tests". For example, if i want to run unit tests only, I don't need to prepare MockAPI.

• Please update Verification Guide.

Note: for local deployment, you may need to change from

{
  throughput: 'ON_DEMAND',
  useDocumentTypes: true
}

to

{
  throughput: { read: 4, write: 2 },
  useDocumentTypes: true
}