remove Microsoft.SourceLink.GitHub (#2047)

not required since sdk 8

https://github.com/dotnet/sourcelink?tab=readme-ov-file#using-source-link-in-net-projects

Author: SimonCropp

Directory.Packages.props

@@ -13,7 +13,6 @@
     <PackageVersion Include="Microsoft.CodeAnalysis.PublicApiAnalyzers" Version="5.0.0-1.25277.114" />
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.4.0" />
     <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.3" />
-    <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="10.0.201" />
     <PackageVersion Include="Microsoft.Testing.Extensions.CodeCoverage" Version="18.6.2" />
     <PackageVersion Include="NSubstitute" Version="5.3.0" />
     <PackageVersion Include="NuGet.Common" Version="6.13.2" />

src/Directory.Build.props

@@ -50,10 +50,6 @@
           Condition="Exists('$(MSBuildProjectDirectory)\\README.md')" />
   </ItemGroup>
 
-  <ItemGroup>
-    <PackageReference Include="Microsoft.SourceLink.GitHub" PrivateAssets="All" />
-  </ItemGroup>
-
   <ItemGroup>
     <AdditionalFiles Include="$(MSBuildProjectDirectory)/PublicAPI/PublicAPI.*.txt" />
     <AdditionalFiles Include="$(MSBuildProjectDirectory)/PublicAPI/$(TargetFramework)/PublicAPI.*.txt" />