Move rest of e2e tests over to new testing framework

[rylev]

This PR moves all e2e tests over to the new testing framework. See #2223 for more details on what this involves.

The e2e tests are not really factored as a testing framework but rather a loose collection of functions that use the lower-level testing framework to build up there tests. There is definitely room for improvement here to make adding e2e tests even easier, but for now, it's a relief to see that writing these tests with the low-level framework is actually fairly straight-forwarded.

As an example, here's the most complicated e2e test we currently have which tests whether running an app from a registry works:

   #[test]
    fn registry_works() -> anyhow::Result<()> {
        // configure that we're using the registry service. this service is backed by a Docker image
        let services = testing_framework::ServicesConfig::new(vec!["registry".into()])?;
        // when determining the args to pass to `spin up` first push the image to the registry
        let spin_up_args = |env: &mut testing_framework::TestEnvironment<()>| {
            let registry_url = format!(
                "localhost:{}/spin-e2e-tests/registry-works/v1",
                env.get_port(5000)?
                    .context("no registry port was exposed by test services")?
            );
            let mut registry_push = std::process::Command::new(spin_binary());
            registry_push.args(&["registry", "push", &registry_url, "--insecure"]);
            env.run_in(&mut registry_push)?;
            Ok(vec![
                "--from-registry".into(),
                registry_url,
                "--insecure".into(),
            ])
        };
        
        // Create a smoke test
        let mut env = bootstrap_smoke_test(
            &services,
            None,
            &[],
            "http-rust",
            |_| Ok(Vec::new()),
            |_| Ok(()),
            spin_up_args,
            testing_framework::SpinMode::Http,
        )?;

         // Assert against the Spin runtime
        assert_spin_request(
            env.runtime_mut(),
            testing_framework::Request::new(reqwest::Method::GET, "/"),
            200,
            &[],
            "Hello, Fermyon",
        )?;
        Ok(())
    }