Add KinD test verifying the source becomes ready

## Overview

We recently found that even though build and unit tests had been passing, the receive adapter panicked when it started when you actually deployed the github source. To address this, we should add a KinD test job that will:
1. Install eventing and the github source
2. Create a github source
3. Verify that the source becomes ready

## More info

These resources will likely be helpful while working on this:
- https://github.com/knative/eventing/blob/main/.github/workflows/kind-e2e.yaml
- https://github.com/knative-extensions/reconciler-test
- https://github.com/knative/eventing/tree/main/test/rekt

Start by reading .github/workflows/kind-e2e.yaml in Knative Eventing, then review the reconciler-test project and test/rekt examples. Set up a KinD job that installs eventing and the GitHub source, creates a GitHubSource resource, and verifies that the source becomes ready.

Written by the indexing model from the issue text.