Refactor end-to-end tests

[nikos912000]

What does this PR do?

• [x] Adds new functionality
• [ ] Alters existing functionality
• [ ] Fixes a bug
• [ ] Improves documentation or testing

Makes the end-to-end tests more generic so they can be executed in non-minikube clusters.

Code Quality Checklist

• [x] The documentation is up to date.
• [x] My code is sufficiently commented and passes continuous integration checks.
• [x] I have signed my commit (see Contributing Docs).

Testing

• [x] I leveraged continuous integration testing
  • [x] by depending on existing unit tests or end-to-end tests.

[nikos912000]

@Devatoria do you think these changes would be valuable? I'm happy to close it if not.