C#: Minor improvements.

Author: michaelnebel

csharp/extractor/Semmle.Extraction.CSharp/CodeAnalysisExtensions/SymbolExtensions.cs

@@ -314,7 +314,6 @@ private static void BuildQualifierAndName(INamedTypeSymbol named, Context cx, Es
             {
                 trapFile.Write(named.Name);
             }
-
         }
 
         private static void BuildTupleId(INamedTypeSymbol named, Context cx, EscapingTextWriter trapFile, ISymbol symbolBeingDefined)

csharp/extractor/Semmle.Extraction.CSharp/Entities/Method.cs

@@ -23,7 +23,7 @@ protected void PopulateParameters()
             if (Symbol.ContainingSymbol is INamedTypeSymbol type &&
                 type.IsExtension && !string.IsNullOrEmpty(type.ExtensionParameter?.Name) &&
                 !Symbol.IsStatic &&
-                Symbol.AssociatedExtensionImplementation is IMethodSymbol associated)
+                Symbol.AssociatedExtensionImplementation is not null)
             {
                 // TODO: Check that this works for generics as well. We might need to also take
                 ImplicitExtensionParameter.Create(Context, this);