Fix deserialization for DFE related types (#5369)

Author: live1206

src/AutoRest.CSharp/Common/Output/Expressions/KnownValueExpressions/JsonSerializerExpression.cs

@@ -17,12 +17,7 @@ public static InvokeStaticMethodExpression Serialize(ValueExpression writer, Val
             return new InvokeStaticMethodExpression(typeof(JsonSerializer), nameof(JsonSerializer.Serialize), arguments);
         }
 
-        public static InvokeStaticMethodExpression Deserialize(JsonElementExpression element, CSharpType serializationType, ValueExpression? options = null)
-        {
-            var arguments = options is null
-                ? new[] { element.GetRawText() }
-                : new[] { element.GetRawText(), options };
-            return new InvokeStaticMethodExpression(typeof(JsonSerializer), nameof(JsonSerializer.Deserialize), arguments, new[] { serializationType });
-        }
+        public static InvokeStaticMethodExpression Deserialize(JsonElementExpression element, CSharpType serializationType)
+            => new InvokeStaticMethodExpression(typeof(JsonSerializer), nameof(JsonSerializer.Deserialize), [element.GetRawText()], [serializationType]);
     }
 }

src/AutoRest.CSharp/Common/Output/Expressions/KnownValueExpressions/ModelReaderWriterExpression.cs

@@ -28,7 +28,7 @@ public static ValueExpression Read(CSharpType type, JsonElementExpression elemen
         {
             if (IsDataFactoryType(type))
             {
-                return JsonSerializerExpression.Deserialize(element, type, options);
+                return JsonSerializerExpression.Deserialize(element, type);
             }
 
             return new InvokeStaticMethodExpression(