THRIFT-4210 include Thrift.45.csproj into CI runs
Client: C#
Patch: Jens Geyer

This closes #1277
diff --git a/lib/csharp/src/Thrift.45.csproj b/lib/csharp/src/Thrift.45.csproj
index 78089fc..455916f 100644
--- a/lib/csharp/src/Thrift.45.csproj
+++ b/lib/csharp/src/Thrift.45.csproj
@@ -17,8 +17,7 @@
   specific language governing permissions and limitations
   under the License.
 -->
-<Project ToolsVersion="12.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
+<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
     <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>