Enable MongoDB transaction support

[amil-i]

Add corresponding configuration. Transactions across multiple operations, collections, databases, documents, and shards, are supported from the version 4.0 but require the mongo instance to be started as a replica set and not standalone.

• https://docs.mongodb.com/manual/core/transactions-operations/
• https://docs.mongodb.com/manual/tutorial/convert-standalone-to-replica-set/