Setup e2e test coverage

Now our e2e test won't actually report the coverage. 

<img width="344" alt="image" src="https://user-images.githubusercontent.com/47812250/184279851-9386ec55-546b-45cb-a30d-6a9c3f4b261e.png">

To implement this, we can ref to how kubevela calculate and report e2e test coverage: https://github.com/kubevela/kubevela/pull/1553