Revert the added assert to the shared analyzer driver as it is only valid for VB.

src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerDriver.cs

@@ -1043,7 +1043,6 @@ private async Task<EventProcessedState> TryProcessSymbolDeclaredAsync(SymbolDecl
                 // Attempt to execute all analyzer actions.
                 var processedState = EventProcessedState.Processed;
                 var symbol = symbolEvent.Symbol;
-                Debug.Assert(symbol.IsInSource());
                 var isGeneratedCodeSymbol = IsGeneratedCodeSymbol(symbol);
 
                 var skipSymbolAnalysis = AnalysisScope.ShouldSkipSymbolAnalysis(symbolEvent);