Remove aspire exclusion (#18663)

Co-authored-by: Viktor Hofer <[email protected]>

Author: mmitche

src/SourceBuild/content/repo-projects/Directory.Build.targets

@@ -42,7 +42,6 @@
     <RepositoryReference Remove="nuget-client" />
     <RepositoryReference Remove="fsharp" />
     <RepositoryReference Remove="vstest" />
-    <RepositoryReference Remove="aspire" />
     <RepositoryReference Remove="installer" />
   </ItemGroup>