Add a GitHub Actions workflow to generate `DIRECTORY.md`

**Description**

To make the algorithm addition process easier, we can make a GitHub Actions workflow to generate a `DIRECTORY.md` file.
Many repositories in the organization do this to keep things organized. We can use the workflow from the [**C++ repository**](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/.github/workflows/awesome_workflow.yml#L49).

What do you think? Thanks. 🙂
