Add sourcelink to nuget package

Author: dakhraui

src/Serilog.AspNetCore/Serilog.AspNetCore.csproj

@@ -18,6 +18,14 @@
     <RepositoryType>git</RepositoryType>
     <GenerateAssemblyVersionAttribute>false</GenerateAssemblyVersionAttribute>
     <RootNamespace>Serilog</RootNamespace>
+  <PropertyGroup>
+
+  </PropertyGroup>
+    <IncludeSymbols>true</IncludeSymbols>
+    <PublishRepositoryUrl>true</PublishRepositoryUrl>
+    <SymbolPackageFormat>snupkg</SymbolPackageFormat>
+    <EmbedUntrackedSources>true</EmbedUntrackedSources>
+    <IsPackable>true</IsPackable>
   </PropertyGroup>
 
   <ItemGroup>
@@ -36,6 +44,10 @@
     <PackageReference Include="Serilog.Sinks.Debug" Version="2.0.0" />
     <PackageReference Include="Serilog.Settings.Configuration" Version="3.3.0" />
     <PackageReference Include="Serilog.Formatting.Compact" Version="1.1.0" />
+    <PackageReference Include="Microsoft.SourceLink.Github" Version="1.1.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">