message: fix
  There was some shared state when the HCM was creating singletons. This clears the map.
  Risk Level: Low
  Testing: Checked bug fix in PR that reproduces
diff: @@ -22,6 +22,7 @@ void UberFilterFuzzer::reset() {
  Event::MockDispatcher& mock_dispatcher =
  dynamic_cast<Event::MockDispatcher&>(read_filter_callbacks_->connection_.dispatcher_);
  mock_dispatcher.clearDeferredDeleteList();
  + factory_context_.admin_.config_tracker_.config_tracker_callbacks_.clear();
  read_filter_.reset();
  }
  @@ -94,7 +95,6 @@ void UberFilterFuzzer::fuzz(
  checkInvalidInputForFuzzer(filter_name, message.get());
  ENVOY_LOG_MISC(info, "Config content after decoded: {}", message->DebugString());
  cb_ = factory.createFilterFactoryFromProto(*message, factory_context_);
  -
  } catch (const EnvoyException& e) {
  ENVOY_LOG_MISC(debug, "Controlled exception in filter setup {}", e.what());
  return;
  