Fix empty string bug

Author: inputfalken

src/DynamoDBGenerator/Internal/MarshallHelper.cs

@@ -59,7 +59,7 @@ public static AttributeValue FromNullableNumberSet<T>(IEnumerable<T?> numbers, s
             return new AttributeValue { NS = [] };
 
         var list = new List<string?>(count);
-        list.AddRange(numbers.Select(x => x.ToString()));
+        list.AddRange(numbers.Select(x => x.ToString()).Where(x => string.IsNullOrEmpty(x) is false));
 
         return new AttributeValue { NS = list };
     }

tests/DynamoDBGenerator.SourceGenerator.Tests/DynamoDBDocumentTests/Marshaller/Asserters/MarshalAsserter.cs

@@ -33,8 +33,11 @@ public void Marshall_IsEquivalentTo_UnmarshallResult()
     public void UnMarshall_IsEquivalentTo_MarshallResult()
     {
         Arguments().Should().AllSatisfy(x =>
-            MarshallImplementation(UnmarshallImplementation(x.attributeValues)).Should()
-                .BeEquivalentTo(x.attributeValues));
+        {
+            var unmarshallImplementation = UnmarshallImplementation(x.attributeValues);
+            var marshallImplementation = MarshallImplementation(unmarshallImplementation);
+            marshallImplementation.Should().BeEquivalentTo(x.attributeValues);
+        });
     }
 
     [Fact]