Update dependency Microsoft.SourceLink.GitHub to v8

Author: renovate[bot]

src/Directory.Build.props

@@ -20,7 +20,7 @@
 		<LangVersion>Latest</LangVersion>
 	</PropertyGroup>
 	<ItemGroup>
-		<PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="All" />
+		<PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All" />
 		<PackageReference Include="TurnerSoftware.BuildVersioning" Version="0.5.0" PrivateAssets="All" />
 	</ItemGroup>