Add Rails Dev Container Templates and Features to Collection Index (#627)

* Add Rails Dev Container Templates and Features

* Update _data/collection-index.yml

Co-authored-by: Rafael Mendonça França <rafael@franca.dev>

* Update _data/collection-index.yml

Co-authored-by: Rafael Mendonça França <rafael@franca.dev>

---------

Co-authored-by: Rafael Mendonça França <rafael@franca.dev>
Co-authored-by: Álvaro Rausell Guiard <33221237+AlvaroRausell@users.noreply.github.com>

Author: 3 people

_data/collection-index.yml

@@ -1280,6 +1280,11 @@
   contact: https://github.com/pairspaces/devcontainers/issues
   repository: https://github.com/pairspaces/devcontainers
   ociReference: ghcr.io/pairspaces/devcontainers/pairspaces
+- name: Rails Dev Container Features
+  maintainer: Rails Core Team
+  contact: https://github.com/rails/devcontainer/issues
+  repository: https://github.com/rails/devcontainer
+  ociReference: ghcr.io/rails/devcontainer/features
 - name: Dev Container Features by Niklas
   maintainer: NLstn
   contact: https://github.com/NLstn/devcontainer-features/issues