good first issue
説明
As seen in code coverage: https://codecov.io/gh/serverless-nextjs/serverless-next.js/tree/master/packages/serverless-components/domain, domain component has 0% coverage.
Adding tests for this should get us from 79% to ~90% overall coverage.
@SarKurd I remember you wanted to add tests for this. Let me know if you are still interested to add tests or someone else can also take it up