Add missing SourceLink properties

Author: panesofglass

src/Directory.Build.props

@@ -10,6 +10,11 @@
     <RepositoryType>git</RepositoryType>
     <RepositoryUrl>https://github.com/xyncro/aether</RepositoryUrl>
     <PackageTags>$(PackageTags);lens;prism;isomorphism;optic;f#;fsharp</PackageTags>
+
+    <!-- SourceLink related properties https://github.com/dotnet/SourceLink#using-sourcelink -->
+    <PublishRepositoryUrl>true</PublishRepositoryUrl>
+    <EmbedUntrackedSources>true</EmbedUntrackedSources>
+    <AllowedOutputExtensionsInPackageBuildOutputFolder>$(AllowedOutputExtensionsInPackageBuildOutputFolder);.pdb</AllowedOutputExtensionsInPackageBuildOutputFolder>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0-*" PrivateAssets="All" />