SponsorLink-enabled analyzers need copylocal

Since otherwise dependencies aren't available and cause failures. Note that on release builds, IL merging happens by default, so no unnecessary extra assemblies are packed or added as analyzer dependencies.

src/SponsorLink/SponsorLink.targets

@@ -7,8 +7,8 @@
     <ShowSponsorLinkInProject Condition="$(ShowSponsorLinkInProject) == '' and '$(TargetFramework)' == 'netstandard2.0'">true</ShowSponsorLinkInProject>
     <!-- This ensures we expose only the main assembly in the Dependencies > Analyzers node -->
     <MergeAnalyzerAssemblies Condition="'$(MergeAnalyzerAssemblies)' == '' and '$(Configuration)' == 'Release'">true</MergeAnalyzerAssemblies>
-    <!-- If we are going to merge files, we need to copy local -->
-    <CopyLocalLockFileAssemblies Condition="'$(MergeAnalyzerAssemblies)' == 'true'">true</CopyLocalLockFileAssemblies>
+    <!-- Whether we merge files or not, dependencies will need to be copy-local -->
+    <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
     <!-- Make Resources visible to intellisense -->
     <CoreCompileDependsOn>CoreResGen;$(CoreCompileDependsOn)</CoreCompileDependsOn>
 
@@ -175,4 +175,12 @@ partial class SponsorLink
     </ItemGroup>
   </Target>
 
+  <!-- Make sure dependencies are available in the package when not merging (i.e. local dev)  -->
+  <Target Name="PackCopyLocalLockFileAssemblies" Condition="'$(MergeAnalyzerAssemblies)' != 'true'" 
+          BeforeTargets="GetPackageContents" DependsOnTargets="ReferenceCopyLocalPathsOutputGroup">
+    <ItemGroup>
+      <PackageFile Include="@(ReferenceCopyLocalPathsOutputGroupOutput)" PackFolder="$(PackFolder)" />
+    </ItemGroup>
+  </Target>
+
 </Project>