Fix missing repository entry (devcontainers#171)

Forgot to add the `repository` link. devcontainers#170 (comment)

Author: jmuchovej

_data/collection-index.yml

@@ -330,5 +330,6 @@
   ociReference: ghcr.io/jasonthedeveloper/features
 - name: Templates by John Muchovej
   maintainer: John Muchovej
-  contact: https://github.com/jmuchovej/devcontainers
+  contact: https://github.com/jmuchovej/devcontainers/issues
+  repository: https://github.com/jmuchovej/devcontainers
   ociReference: ghcr.io/jmuchovej/templates