Nuget package 'build' folder content updated

Author: alex-kulakov

…ontent/build/net5.0/Xtensive.Orm.targets …ontent/build/net7.0/Xtensive.Orm.targetsOrm/Xtensive.Orm/NuGetContent/build/net5.0/Xtensive.Orm.targets renamed to Orm/Xtensive.Orm/NuGetContent/build/net7.0/Xtensive.Orm.targets Orm/Xtensive.Orm/NuGetContent/build/net5.0/Xtensive.Orm.targets renamed to Orm/Xtensive.Orm/NuGetContent/build/net7.0/Xtensive.Orm.targets

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  Copyright (C) 2011-2013 Xtensive LLC.
+  All rights reserved.
+  For conditions of distribution and use, see license.
+-->
+
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+
+<Import Project="$(MSBuildThisFileDirectory)..\..\DataObjects.Net.targets" />
+
+</Project>