findAndUpdate: change the default new to true by default on mongoose?

[AbdelrahmanHafez]

We could introduce a breaking change in 6.0 and make findOneAndUpdate have new option set to true by default, after implementing #9183 we will be giving users the option to change that behavior if they prefer.

I believe the majority of users would prefer to have the updated document returned from findOneAndUpdate by default.

Thoughts? @vkarpov15

[vkarpov15]

We changed new to false by default in 4.0 to be consistent with the MongoDB driver - all other MDB clients use new: false behavior by default, so I think we should err on the side of keeping it consistent. I like the idea of making it a globally configurable default like you suggested in #9183 though.

[AbdelrahmanHafez]

Ah, weird default from MongoDB, never seen a single findOneAndUpdate(...) out there that wasn't using { new: true } unless it was missing by mistake.

IMO, it's more intuitive to have new: true by default, but I agree that we should be consistent with the MongoDB driver as long as we can globally configure it.