Bump Microsoft.SourceLink.GitHub from 1.1.1 to 8.0.0 (#1455)

Bumps [Microsoft.SourceLink.GitHub](https://github.com/dotnet/sourcelink) from 1.1.1 to 8.0.0.
- [Release notes](https://github.com/dotnet/sourcelink/releases)
- [Commits](https://github.com/dotnet/sourcelink/commits)

---
updated-dependencies:
- dependency-name: Microsoft.SourceLink.GitHub
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Directory.Build.targets

@@ -3,7 +3,7 @@
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118" PrivateAssets="all" />
     <PackageReference Include="Microsoft.CodeAnalysis.NetAnalyzers" Version="7.0.4" PrivateAssets="all" />
     <PackageReference Include="Nerdbank.GitVersioning" Version="3.6.133" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="All" />
+    <PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All" />
   </ItemGroup>
 
   <ItemGroup>