message: x-ms-client-name case insensitive match with prop name
diff: @@ -53,7 +53,7 @@ namespace AutoRest.Swagger.Validation
  if ((property.Value?.Extensions?.Count ?? 0) != 0)
  {
  string valueOfXmsExtensionProperty = (string)property.Value.Extensions.GetValueOrNull(extensionToCheck);
  - if (valueOfXmsExtensionProperty != null && valueOfXmsExtensionProperty.EqualsIgnoreCase(property.Key))
  + if (valueOfXmsExtensionProperty != null && valueOfXmsExtensionProperty.Equals(property.Key))
  {
  yield return new ValidationMessage(new FileObjectPath(context.File, context.Path), this, property.Key);
  }
  