Merge pull request #13420 from tamasvajk/feature/standalone-mscorlib

C#: Make sure System.Private.CoreLib is added only once as a reference in standalone extraction

csharp/extractor/Semmle.Extraction.CSharp.Standalone/BuildAnalysis.cs

@@ -120,13 +120,13 @@ namespace Semmle.BuildAnalyser
                     UseReference(filename);
             }
 
-            ResolveConflicts();
-
             if (options.UseMscorlib)
             {
                 UseReference(typeof(object).Assembly.Location);
             }
 
+            ResolveConflicts();
+
             // Output the findings
             foreach (var r in usedReferences.Keys)
             {