Adds traceMode evaluator setting to support trace() pretty printing (#1100)

docs/src/test/kotlin/DocSnippetTests.kt

@@ -97,6 +97,7 @@ class DocSnippetTestsEngine : HierarchicalTestEngine<DocSnippetTestsEngine.Execu
       IoUtils.getCurrentWorkingDir(),
       StackFrameTransformers.defaultTransformer,
       false,
+      null
     )
     return ExecutionContext(replServer)
   }