feat(topics): add sorting to topics requests

- Add descending sort by name to readAll and readAfter methods in topics requests
- Update made in TopicsFilterBloc class

Author: fulleni

lib/headlines-feed/bloc/topics_filter_bloc.dart

@@ -54,6 +54,7 @@ class TopicsFilterBloc extends Bloc<TopicsFilterEvent, TopicsFilterState> {
     try {
       final response = await _topicsRepository.readAll(
         pagination: const PaginationOptions(limit: _topicsLimit),
+        sort: [const SortOption('name', SortOrder.desc)],
       );
       emit(
         state.copyWith(
@@ -87,6 +88,7 @@ class TopicsFilterBloc extends Bloc<TopicsFilterEvent, TopicsFilterState> {
           limit: _topicsLimit,
           cursor: state.cursor,
         ),
+        sort: [const SortOption('name', SortOrder.desc)],
       );
       emit(
         state.copyWith(