Generate unit tests in runtime/compile time.

[guilhermelhr]

We should look into a way to generate these tests in runtime or compile time.

Originally posted by @guilhermelhr in https://github.com/guilhermelhr/unityro/issues/11#issuecomment-735288334

[guilhermelhr]

Currently we read the maplist and generate a file with tests for each map, then copy it back to C# and execute them. Since GRFs could contain different maps, it would be desirable to have this be done automatically.

[Danil0v3s]

Another option is to have a single test iterating through the map list and loading them. However the time to execute this would be huge, but threading that could help a bit