code: public function getAll()
      {
          $queryBuilder = $this->connection->createQueryBuilder();
          $queryBuilder->from($this->table, 'config');
          $queryBuilder->select([
              'config.name',
              'config.value',
          ]);
  
          $configElements = $queryBuilder->execute()->fetchAll();
  
          $result = [];
  
          foreach ($configElements as $element) {
              $result[$element['name']] = $element['value'];
          }
  
          return $result;
      }
docs: {@inheritdoc}