VM: reduce test noise and improve test output

[petar-dambovaliev]

Running GNOVM tests is very noisy.
It makes looking for valuable information difficult.

Tests that are passing should not say anything except their name.
The only stack trace in the output should be in a failing test.
Tests that are designed to fail (failing means they succeed) should not output a stack trace.
The testing code also in case of failure can provide wrong information about what the problem is.
That can make it so you have to debug the testing code first, to find what the actual problem is and then debug your code.

This would reduce potential friction in any issue worked on in the future.