Add UNSW COMP3231 OS Development Template (devcontainers#153)

* Update collection-index.yml

* Update _data/collection-index.yml

Co-authored-by: Samruddhi Khandale <skhandale@microsoft.com>

---------

Co-authored-by: Samruddhi Khandale <skhandale@microsoft.com>

Author: HamishWHC

_data/collection-index.yml

@@ -282,4 +282,9 @@
   maintainer: Swift Server Workgroup
   contact: https://github.com/swift-server/swift-devcontainer-template/issues
   repository: https://github.com/swift-server/swift-devcontainer-template
-  ociReference: ghcr.io/swift-server/swift-devcontainer-template
+  ociReference: ghcr.io/swift-server/swift-devcontainer-template
+- name: UNSW cs3231 OS Development
+  maintainer: Hamish Cox
+  contact: https://github.com/HamishWHC/cs3231-devcontainer/issues
+  repository: https://github.com/HamishWHC/cs3231-devcontainer
+  ociReference: ghcr.io/hamishwhc/cs3231-devcontainer