Update EntityFrameworkCoreXmlRepository.cs

src/DataProtection/EntityFrameworkCore/src/EntityFrameworkCoreXmlRepository.cs

@@ -42,6 +42,7 @@ public virtual IReadOnlyCollection<XElement> GetAllElements()
         {
             using (var scope = _services.CreateScope())
             {
+                var context = scope.ServiceProvider.GetRequiredService<TContext>();	
                 // Put logger in a local such that `this` isn't captured.
                 var logger = _logger;
                 return context.DataProtectionKeys.AsNoTracking().Select(key => TryParseKeyXml(key.Xml, logger)).ToList().AsReadOnly();