Update packages.

Author: Berrysoft

samples/Berrysoft.Data.TreeSample/Berrysoft.Data.TreeSample.csproj

@@ -5,16 +5,12 @@
     <TargetFramework>netcoreapp2.0</TargetFramework>
   </PropertyGroup>
 
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
-    <LangVersion>latest</LangVersion>
-  </PropertyGroup>
-
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
+  <PropertyGroup>
     <LangVersion>latest</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="System.Memory" Version="4.5.0-rc1" />
+    <PackageReference Include="System.Memory" Version="4.5.0" />
   </ItemGroup>
 
   <ItemGroup>