Fix the "Turkish İ" problem

The following tests fail on a platform having Turkish specific
settings:

* SA1300UnitTests.TestLowerCaseInterfaceMembersAsync
* SA1312UnitTests.TestRenameConflictsWithKeywordAsync
* SA1313UnitTests.TestRenameConflictsWithKeywordAsync

That's bacause upper(i) gives "İ" and lower(I) gives "ı" in Turkish.
(More info: https://haacked.com/archive/2012/07/05/turkish-i-problem-and-why-you-should-care.aspx/)

This fix adds UseCulture attribute to those problematic classes.

Author: monoblaine

StyleCop.Analyzers/StyleCop.Analyzers.Test/NamingRules/SA1300UnitTests.cs

@@ -9,9 +9,11 @@ namespace StyleCop.Analyzers.Test.NamingRules
     using Microsoft.CodeAnalysis.CodeFixes;
     using Microsoft.CodeAnalysis.Diagnostics;
     using StyleCop.Analyzers.NamingRules;
+    using StyleCop.Analyzers.Test.Helpers;
     using TestHelper;
     using Xunit;
 
+    [UseCulture("en-US")]
     public class SA1300UnitTests : CodeFixVerifier
     {
         [Fact]

StyleCop.Analyzers/StyleCop.Analyzers.Test/NamingRules/SA1312UnitTests.cs

@@ -9,9 +9,11 @@ namespace StyleCop.Analyzers.Test.NamingRules
     using Microsoft.CodeAnalysis.CodeFixes;
     using Microsoft.CodeAnalysis.Diagnostics;
     using StyleCop.Analyzers.NamingRules;
+    using StyleCop.Analyzers.Test.Helpers;
     using TestHelper;
     using Xunit;
 
+    [UseCulture("en-US")]
     public class SA1312UnitTests : CodeFixVerifier
     {
         [Fact]

StyleCop.Analyzers/StyleCop.Analyzers.Test/NamingRules/SA1313UnitTests.cs

@@ -9,9 +9,11 @@ namespace StyleCop.Analyzers.Test.NamingRules
     using Microsoft.CodeAnalysis.CodeFixes;
     using Microsoft.CodeAnalysis.Diagnostics;
     using StyleCop.Analyzers.NamingRules;
+    using StyleCop.Analyzers.Test.Helpers;
     using TestHelper;
     using Xunit;
 
+    [UseCulture("en-US")]
     public class SA1313UnitTests : CodeFixVerifier
     {
         [Fact]