Support for ConcordionRunner subclasses

[fiq]

Issue classes which extends ConcordionRunner

I found that using a JUnit runner which extends ConcordionRunner breaks navigation within the plugin. I can still run the fixture, but the plugin highlights that Test plugin is not annotated with @RunWith(ConcordionRunner.class)

The markdown displays the Concordion icon and allows navigation back to the fixture, but does not provide the usual menu option for running the fixture directly.

Eg.
public class SpecificationWithFrillsRunner extends ConcordionRunner{.. declared with @RunWith(SpecificationWithFrillsRunner.class) public class SpecFixtures produces :
Produces:

Versions

Plugin version: 0.12.0
IntelliJ Version: 2020.2.2
Concordion version: 3.0.1