Fix GitHub Apple Release Pipeline

Our GitHub Actions workflow—written in a single `.yml` file—should kick in every time code hits the `main` branch, build the iOS project, then automatically upload the resulting archive to Apple Developer for TestFlight distribution... (Budget: $10 - $30 USD, Jobs: CI/CD, Continuous Integration, DevOps, Git, iOS Development, iPad, Mobile App Development, Objective C, Swift, Xcode)