updating DIRECTORY.md

Author: github-actions

DIRECTORY.md

@@ -63,6 +63,8 @@
  * Disjoint Sets
  * [Disjoint Sets](https://github.com/TheAlgorithms/Ruby/blob/master/data_structures/disjoint_sets/disjoint_sets.rb)
  * Graphs
+ * [Bfs](https://github.com/TheAlgorithms/Ruby/blob/master/data_structures/graphs/bfs.rb)
+ * [Bfs Test](https://github.com/TheAlgorithms/Ruby/blob/master/data_structures/graphs/bfs_test.rb)
  * [Topological Sort](https://github.com/TheAlgorithms/Ruby/blob/master/data_structures/graphs/topological_sort.rb)
  * [Topological Sort Test](https://github.com/TheAlgorithms/Ruby/blob/master/data_structures/graphs/topological_sort_test.rb)
  * [Unweighted Graph](https://github.com/TheAlgorithms/Ruby/blob/master/data_structures/graphs/unweighted_graph.rb)