Test Runner v2

[sgammon]

We need a new architecture for our test runner which is decoupled from GraalVM's polyglot types.

This is driven by the need to support several JVM targets within our runners; when espresso can't be loaded (in static circumstances, where unsupported, etc) it is a useful feature to fallback to regular JVM execution.

We can already do this in the regular runner, but we can't yet for tests.

Architecturally this should be possible because the concept of a test isn't itself coupled to polyglot types. With a rewrite, we could make different choices about our approach.

• Test Runner v2 Architecture
  • Research driving it with Jupiter
  • Decouple from polyglot types
  • Support execution listeners