Return directories/folders in repository file finder results
Originally from https://gitlab.com/gitlab-org/gitlab/-/issues/27514
### Proposal
When using the file finder ([example](https://gitlab.com/gitlab-org/gitlab/-/find_file/master)), return not only the matching file names but also directory/folder names.
Today, in the GitLab project, if you type “views”, you get view specs (file name) and no results for the [`views` directory](https://gitlab.com/gitlab-org/gitlab/-/tree/master/app/views).

<!-- Label reminders
Use the following resources to find the appropriate labels:
- https://gitlab.com/gitlab-org/gitlab/-/labels
- https://about.gitlab.com/handbook/product/categories/features/
-->
issue