Add neotest-based tests for NNS wrapper

[AnnaShaleva]

Is your feature request related to a problem? Please describe.

After #3291 it's possible that some bugs are left in NNS wrapper.

Describe the solution you'd like

It would be nice to add the following test to NNS wrapper: download NNS manifest/NEF from N3 mainnet and use these static bytes to deploy NNS to neotest environment. After that create a set of tests using this "copy" of NNS.