Fix MongoDB DeprecationWarning: collection.findOneAndUpdate option [returnOriginal]
CONTEXT: RateLimiterMongo works without warning for Mongo Client v4+ with [this check](https://github.com/animir/node-rate-limiter-flexible/blob/master/lib/RateLimiterMongo.js#L172). But deprecation was introduced before v4, so some v3.x affected also.

TODO: Find exact version, when deprecation is added and improve mongoDB driver version check in [the condition](https://github.com/animir/node-rate-limiter-flexible/blob/master/lib/RateLimiterMongo.js#L172).