Rename TestBaseTypeDeclarationAsync to TestNamespaceDeclarationAsync

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers.Test/ReadabilityRules/SA1137UnitTests.cs

@@ -22,9 +22,8 @@ public class SA1137UnitTests : CodeFixVerifier
         [InlineData("struct")]
         [InlineData("interface")]
         [InlineData("enum")]
-        public async Task TestBaseTypeDeclarationAsync(string baseTypeKind)
+        public async Task TestNamespaceDeclarationAsync(string baseTypeKind)
         {
-            // Need to test attribute lists here
             string testCode = $@"
 using System;