addDiagnostics method
Adds all newDiagnostics to EvaluationMetric.diagnostics.
Implementation
void addDiagnostics(Iterable<EvaluationDiagnostic> newDiagnostics) {
final list = newDiagnostics.toList();
if (list.isEmpty) return;
diagnostics ??= [];
diagnostics!.addAll(list);
}