Fix issues from trimming support commit

Author: SamboyCoding

Tomlet.Tests/ObjectToStringTests.cs

@@ -106,10 +106,10 @@ public void SerializingAnEmptyObjectGivesAnEmptyString()
         }
 
         [Fact]
-        public void AttemptingToDirectlySerializeNullThrows()
+        public void AttemptingToDirectlySerializeNullReturnsNull()
         {
             //We need to use a type of T that actually has something to serialize
-            Assert.Throws<ArgumentNullException>(() => TomletMain.DocumentFrom(typeof(SimplePrimitiveTestClass), null!, null));
+            Assert.Null(TomletMain.DocumentFrom(typeof(SimplePrimitiveTestClass), null!, null));
         }
     }
 }

Tomlet.Tests/Tomlet.Tests.csproj

@@ -1,9 +1,10 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFramework>net7</TargetFramework>
+        <TargetFramework>net9</TargetFramework>
         <IsPackable>false</IsPackable>
         <LangVersion>11</LangVersion>
+        <IsTrimmable>false</IsTrimmable>
     </PropertyGroup>
 
     <ItemGroup>

Tomlet/TomletMain.cs

@@ -69,6 +69,7 @@ public static object To(Type what, TomlValue value, TomlSerializerOptions? optio
 
 #if MODERN_DOTNET
     [return: NotNullIfNotNull("t")]
+    [UnconditionalSuppressMessage("AOT", "IL2072", Justification = "Any object that is being serialized must have been in the consuming code in order for this call to be occurring, so the dynamic code requirement is already satisfied.")]
 #if NET7_0_OR_GREATER
     [RequiresDynamicCode("The native code for underlying implementations of serialize helper methods may not be available for a given type.")]
 #endif // NET7_0_OR_GREATER
@@ -80,7 +81,7 @@ public static object To(Type what, TomlValue value, TomlSerializerOptions? optio
         if (t == null)
             return null;
 
-        return ValueFrom(typeof(T), t, options);
+        return ValueFrom(t.GetType(), t, options);
     }
 
 #if MODERN_DOTNET