Port lwip tests to use the Unikraft testing API

[StefanJum]

Port the lwip tests to use uktest, the Unikraft testing API.
You can follow the libsodium ported tests as an example and check the USoC testing session for support.

Check the website and the uktest README and api for instructions on how to write tests.

Hackathon points: 40 points per test suite (e.g. 40 points for porting test/unit/dhcp).

[b1shtream]

Working on it!

[b1shtream]

@StefanJum Link to the website and testing session are not found

[StefanJum]

Indeed @chococandy63, sorry for that. You can use the PR here as an example, along with the API docs in the uktest README file. We will bring back the testing session soon hopefully.