allCollections method
Reads all collections https://www.arangodb.com/docs/3.4/http/collection-getting.html#reads-all-collections
Implementation
Future<ResultResponse<List<CollectionInfo>>> allCollections() async {
final answer = await _httpGet(['_db', db, '_api', 'collection']);
final result = _toResultResponse(answer, _toCollectionListResponse);
return result;
}