add Couper devcontainer feature to the index (#614)

Co-authored-by: Álvaro Rausell Guiard <33221237+AlvaroRausell@users.noreply.github.com>

Author: malud

_data/collection-index.yml

@@ -1184,7 +1184,7 @@
   maintainer: Pedro Rodrigues
   contact: https://github.com/pirpedro/features/issues
   repository: https://github.com/pirpedro/features
-  ociReference: ghcr.io/pirpedro/features  
+  ociReference: ghcr.io/pirpedro/features
 - name: Dev container features for Azure linux images
   maintainer: Victor Maznev
   contact: https://github.com/bullmastiffo/devcontainers-features/issues
@@ -1275,6 +1275,11 @@
   contact: https://github.com/pairspaces/devcontainers/issues
   repository: https://github.com/pairspaces/devcontainers
   ociReference: ghcr.io/pairspaces/devcontainers/pairspaces
+- name: Couper DevContainer Feature
+  maintainer: Marcel Ludwig (malud)
+  contact: https://github.com/coupergateway/features/issues
+  repository: https://github.com/coupergateway/features
+  ociReference: ghcr.io/coupergateway/features
 - name: EstebenR Devcontainers
   maintainer: EstebenR (Papabos)
   contact: https://github.com/EstebenR/devcontainers/issues