Remove unused code (#23691)

Remove an unused private method and an unused local variable.

src/Features/JsonPatch/src/JsonPatchDocumentOfT.cs

@@ -859,15 +859,6 @@ namespace Microsoft.AspNetCore.JsonPatch
             return null;
         }
 
-        private static bool ContinueWithSubPath(ExpressionType expressionType)
-        {
-            return (expressionType == ExpressionType.ArrayIndex
-                || expressionType == ExpressionType.Call
-                || expressionType == ExpressionType.Convert
-                || expressionType == ExpressionType.MemberAccess);
-
-        }
-
         // Evaluates the value of the key or index which may be an int or a string,
         // or some other expression type.
         // The expression is converted to a delegate and the result of executing the delegate is returned as a string.

src/Hosting/Hosting/src/StaticWebAssets/StaticWebAssetsLoader.cs

@@ -34,7 +34,6 @@ namespace Microsoft.AspNetCore.Hosting.StaticWebAssets
 
         internal static void UseStaticWebAssetsCore(IWebHostEnvironment environment, Stream manifest)
         {
-            var staticWebAssetsFileProvider = new List<IFileProvider>();
             var webRootFileProvider = environment.WebRootFileProvider;
 
             var additionalFiles = StaticWebAssetsReader.Parse(manifest)