Add Keeper Secrets Manager Dev Container Features (#698)

* Add Keeper Secrets Manager Dev Container Features

* Fix ociReference formatting in collection-index.yml

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Co-authored-by: Abdurrahmaan Iqbal <abdurriq@github.com>

Author: chrisdemers

_data/collection-index.yml

@@ -1491,6 +1491,11 @@
   contact: https://github.com/doughatcher/devcontainer-templates/issues
   repository: https://github.com/doughatcher/devcontainer-templates
   ociReference: ghcr.io/doughatcher/devcontainer-templates
+- name: Keeper Secrets Manager (KSM) Dev Container Features
+  maintainer: cdsolinfo
+  contact: https://github.com/cdsolinfo/devcontainer-features/issues
+  repository: https://github.com/cdsolinfo/devcontainer-features
+  ociReference: ghcr.io/cdsolinfo/devcontainer-features  
 - name: Devcontainer Features by nkaaf
   maintainer: nkaaf
   contact: https://github.com/nkaaf/devcontainer-features/issues