Enable SA1133 by default

Fixes #1827

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers/ReadabilityRules/SA1133DoNotCombineAttributes.cs

@@ -26,7 +26,7 @@ internal class SA1133DoNotCombineAttributes : DiagnosticAnalyzer
         private static readonly string HelpLink = "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/blob/master/documentation/SA1133.md";
 
         private static readonly DiagnosticDescriptor Descriptor =
-            new DiagnosticDescriptor(DiagnosticId, Title, MessageFormat, AnalyzerCategory.ReadabilityRules, DiagnosticSeverity.Warning, AnalyzerConstants.DisabledNoTests, Description, HelpLink);
+            new DiagnosticDescriptor(DiagnosticId, Title, MessageFormat, AnalyzerCategory.ReadabilityRules, DiagnosticSeverity.Warning, AnalyzerConstants.EnabledByDefault, Description, HelpLink);
 
         private static readonly Action<CompilationStartAnalysisContext> CompilationStartAction = HandleCompilationStart;
         private static readonly Action<SyntaxNodeAnalysisContext> HandleAttributeListAction = HandleAttributeList;