[Build] Upgraded NetAnalyzers to 7.0.1 (#24792)

* upgraded NetAnalyzers to 7.0.1

* fix spellcheck

* Microsoft.CodeAnalysis.NetAnalyzers 7.0.1

* rebase and fix

src/modules/poweraccent/PowerAccent.Core/Languages.cs

@@ -2,9 +2,7 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
 using PowerToys.PowerAccentKeyboardService;
-using Windows.Globalization;
 
 namespace PowerAccent.Core
 {
@@ -42,7 +40,7 @@ namespace PowerAccent.Core
         TK,
     }
 
-    internal class Languages
+    internal sealed class Languages
     {
         public static string[] GetDefaultLetterKey(LetterKey letter, Language lang)
         {