chore: change to openbao-plugin-secrets-litellm (#479)

change to openbao litellm plugin as it installs to the correct directory

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Co-authored-by: Ben Vincent <ben@unkin.net>
Reviewed-on: #479

hieradata/roles/infra/storage/vault.yaml

@@ -28,4 +28,4 @@ profiles::nginx::simpleproxy::proxy_path: '/'
 
 profiles::packages::include:
   openbao-plugins: {}
-  vault-plugin-secrets-litellm: {}
+  openbao-plugin-secrets-litellm: {}