Test Runner Not Detecting Equal DateTimes (+00:00 vs Z)

When running the test CqlArithmeticFunctionsTest:MaxValue:DateTimeMaxValue, the test runner reports:

Test CqlArithmeticFunctionsTest:MaxValue:DateTimeMaxValue status: fail expected: @9999-12-31T23:59:59.999Z actual: @9999-12-31T23:59:59.999+00:00

My engine is returning the following result:

{
  "resourceType": "Parameters",
  "parameters": [
    {
      "extension": [
        {
          "url": "http://hl7.org/fhir/StructureDefinition/cqf-cqlType",
          "valueString": "System.DateTime"
        }
      ],
      "name": "return",
      "valueDateTime": "9999-12-31T23:59:59.999+00:00"
    }
  ]
}

I suspect that the issue is that my DateTime uses offset +00:00, but the runner is expecting Z. Since these are equivalent, the runner should detect them as equal.

Start by running CqlArithmeticFunctionsTest:MaxValue:DateTimeMaxValue and trace the test runner's DateTime comparison for the reported expected and actual values. Done means equivalent UTC representations such as Z and +00:00 are treated as equal without changing the CQL result.