build(deps): bump Microsoft.SourceLink.GitHub (#422)

Bumps [Microsoft.SourceLink.GitHub](https://github.com/dotnet/sourcelink) from 1.0.0-beta2-19367-01 to 1.0.0-beta2-19554-01.
- [Release notes](https://github.com/dotnet/sourcelink/releases)
- [Commits](dotnet/sourcelink@1.0.0-beta2-19367-01...1.0.0-beta2-19554-01)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

src/Directory.build.props

@@ -50,7 +50,7 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(IsTestProject)' != 'true' and '$(SourceLinkEnabled)' != 'false'">
-    <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0-beta2-19367-01" PrivateAssets="All" /> 
+    <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.0.0-beta2-19554-01" PrivateAssets="All" /> 
   </ItemGroup>
 
    <PropertyGroup>