Only include GitVersionCore.pdb if it exists (which it won't on Linux)

Author: asbjornu

src/GitVersionCore/GitVersionCore.csproj

@@ -199,11 +199,11 @@
     <!-- NugetRefBuild -->
     <MakeDir Directories="$(SolutionDir)NuGetRefBuild\lib\Net45" />
     <Copy SourceFiles="$(OutputPath)GitVersionCore.dll" DestinationFolder="$(BuildDir)NuGetRefBuild\lib\Net45" />
-    <Copy SourceFiles="$(OutputPath)GitVersionCore.pdb" DestinationFolder="$(BuildDir)NuGetRefBuild\lib\Net45" />
+    <Copy SourceFiles="$(OutputPath)GitVersionCore.pdb" DestinationFolder="$(BuildDir)NuGetRefBuild\lib\Net45" Condition="Exists('$(OutputPath)GitVersionCore.pdb')" />
     <Copy SourceFiles="$(OutputPath)GitVersionCore.xml" DestinationFolder="$(BuildDir)NuGetRefBuild\lib\Net45" />
     <Copy SourceFiles="$(ProjectDir)NugetAssets\GitVersion.nuspec" DestinationFolder="$(BuildDir)NuGetRefBuild" />
     <PepitaPackage.CreatePackageTask NuGetBuildDirectory="$(BuildDir)NuGetRefBuild" MetadataAssembly="$(OutputPath)GitVersionCore.dll" Version="$(GitVersion_NuGetVersion)" />
   </Target>
   <Import Project="..\packages\PepitaPackage.1.21.4\build\PepitaPackage.targets" Condition="Exists('..\packages\PepitaPackage.1.21.4\build\PepitaPackage.targets')" />
   <Import Project="..\packages\Fody.1.29.4\build\portable-net+sl+win+wpa+wp\Fody.targets" Condition="Exists('..\packages\Fody.1.29.4\build\portable-net+sl+win+wpa+wp\Fody.targets')" />
-</Project>
+</Project>