Cleanup unnecessary files added during 2.2 => master merge (#9690)

eng/scripts/CodeCheck.ps1

@@ -143,7 +143,7 @@ try {
     if ($changedFiles) {
         foreach ($file in $changedFiles) {
             $filePath = Resolve-Path "${repoRoot}/${file}"
-            LogError "Generated code is not up to date in $file." -filepath $filePath
+            LogError "Generated code is not up to date in $file. You might need to regenerate the reference assemblies or project list (see docs/ReferenceAssemblies.md and docs/ReferenceResolution.md)" -filepath $filePath
             & git --no-pager diff --ignore-space-at-eol $filePath
         }
     }