E2E Testing enhancements

There are a number of areas where the e2e testing process can be improved.

All of these issues would make good starter issues to work on.

| Enhancement | Assigned To | Status |
| -------------------- | ------------------ | --------- |
| Setting CERT_MANAGER_INSTALL_SKIP=true and PROMETHEUS_INSTALL_SKIP=true does not stop deployment of these items | | Not Started |
| Documentation for using local setup and running e2e tests does not exist | sdbrett | Not Started |
| The tear down process deletes the kind cluster but has also has steps to cleanup within the cluster | | Not Started |
| Add option to stop tear down process so testers can perform manual checks which can help with building tests | | Not Started |
| Add option to use existing clusters, this can reduce the time to run tests as cluster build and tear down are not needed for each test run | | Not Started |
| Arguments such as IMG, CERT_MANAGER_INSTALL_SKIP and PROMETHEUS_INSTALL_SKIP are not passed to `go test`. Currently this means setting IMG also means that a tester needs to set the value of the `imageName` variable to match. This is also related to INSTALL_SKIP options not working. | | Not Started |
| Sending sigint() should trigger the cleanup process. | | Not Started |