add a generic ReferenceReturningMethod class

Author: Elektryk-Andrzej

MethodSystem/BaseMethods/ReferenceReturningMethod.cs

@@ -8,4 +8,14 @@ namespace SER.MethodSystem.BaseMethods;
 public abstract class ReferenceReturningMethod : ReturningMethod<ReferenceValue>
 {
     public abstract Type ReturnType { get; }
+}
+
+public abstract class ReferenceReturningMethod<T> : ReferenceReturningMethod
+{
+    public override Type ReturnType => typeof(T);
+
+    protected new T ReturnValue
+    {
+        set => base.ReturnValue = new ReferenceValue(value);
+    }
 }