[Feature] Hide internal database structure

[danieldanielecki]

In the #60 an Azure CosmosDB has been introduced as a backup database for GitHub. However, security-wise it's not perfect, because exposing internal database structure like container names and partition key paths is a security risk.

Make improvements related to the database structure in terms of security here, and change examId, exposed questions, maybe also id, and the rest looks oke.

Then recreate the database in Azure.