moved logo ref to correctl location

Author: egil

src/AngleSharp.Diffing/AngleSharp.Diffing.csproj

@@ -49,7 +49,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <None Include="..\..\docs\logo.png" Pack="true" PackagePath="\" />
+    <None Include="..\..\logo.png" Pack="true" PackagePath="\" />
     <None Include="..\..\LICENSE" Pack="true" PackagePath="\" />
   </ItemGroup>