Fix failing tests and test network

[Semisol]

This PR fixes some tests that failed due to the schema generator and the changed Network interface. This PR makes 2 changes to the (unused) testnetwork functionality:

• The opts field is now fixed for each vat in the test network.
  • This should be suitable for testing purposes, and it is expected that most applications are not changing their options per client.
  • There was also no way with the previous way to choose the options knowing the remote peer ID, meaning such a use case could not be simulated with the test network anyway.
• The incomplete 3PH functionality is removed.
  • This should be re-added to match the new interface for tests in the same PR as the first implementation of 3PH.

[lthibault]

LGTM. Thanks again!