[CI] test against the parachain (Zombienet)

[clangenb]

It should not be that hard to test against a zombienet set up of the parachain.

We can simply translate this workflow for the setup: https://github.com/encointer/encointer-parachain/blob/d4370b7227e4e4e08188d293c62ecc2195efe7e4/.github/workflows/ci.yml#L129

[clangenb]

But beware: it could be unstable, the python tests in the parachain repository are also unstable.

[brenzi]

Zombienet is known to be unstable. Maybe chopsticks would be a better maintainable option for XCM?