bump dotnet sdk version

Author: josecorella

DynamoDbEncryption/runtimes/net/DynamoDbEncryption.csproj

@@ -58,7 +58,7 @@
 
   <ItemGroup>
     <PackageReference Include="AWSSDK.DynamoDBv2" Version="3.7.303.14"/>
-    <PackageReference Include="AWSSDK.Core" Version="3.7.304.7"/>
+    <PackageReference Include="AWSSDK.Core" Version="3.7.304.16"/>
     <PackageReference Include="DafnyRuntime" Version="$(DafnyVersion)" />
     <ProjectReference Include="../../../submodules/MaterialProviders/AwsCryptographicMaterialProviders/runtimes/net/MPL.csproj"/>
     <!--