fix(csharp): Fix packing process (apache#1862)

Closes apache#1861

csharp/Directory.Build.props

@@ -27,7 +27,7 @@
   <!-- AssemblyInfo properties -->
   <PropertyGroup>
     <Product>Apache Arrow ADBC library</Product>
-    <Copyright>Copyright 2022-2023 The Apache Software Foundation</Copyright>
+    <Copyright>Copyright 2022-2024 The Apache Software Foundation</Copyright>
     <Company>The Apache Software Foundation</Company>
     <Version>1.0.0</Version>
   </PropertyGroup>
@@ -46,7 +46,7 @@
   <!-- NuGet properties -->
   <PropertyGroup>
     <Authors>The Apache Software Foundation</Authors>
-    <PackageIconUrl>https://www.apache.org/images/feather.png</PackageIconUrl>
+    <PackageIcon>feather.png</PackageIcon>
     <!-- We can't use PackageLicenseExpression; the license file also contains 3rd-party notices. -->
     <PackageLicenseFile>LICENSE.txt</PackageLicenseFile>
     <PackageProjectUrl>https://arrow.apache.org/</PackageProjectUrl>
@@ -59,6 +59,7 @@
 
   <ItemGroup Condition="'$(IsPackable)' == 'true'">
     <Content Include="$(RepoRoot)LICENSE.txt" Pack="true" PackagePath="" />
+    <Content Include="$(CSharpDir)/feather.png" Link="feather.png" Pack="true" PackagePath="\" />
   </ItemGroup>
 
 </Project>