perf(document): avoid cloning options using spread operator for perf reasons

[vkarpov15]

Re: #14394

Summary

3x perf improvement on benchmark with this one weird trick. Without this PR:

$ node gh-14394.js 
Num docs 200 200
toObject ms: 1141
{
  _id: new ObjectId('66365214acdcbc00eacbd721'),
  name: 'test child 0_0',
  parentId: new ObjectId('66365214acdcbc00eacbd71f'),
  __v: 0
}
Done

With this PR:

$ node gh-14394.js 
Num docs 200 200
toObject ms: 492
{
  _id: new ObjectId('66365214acdcbc00eacbd721'),
  name: 'test child 0_0',
  parentId: new ObjectId('66365214acdcbc00eacbd71f'),
  __v: 0
}
Done

Not sure why this is so much faster, but still works and makes $toObject() that much faster 🤷‍♂️

Examples

[vkarpov15]

f087e8f includes a similar, but smaller speedup. After this change:

$ node gh-14394.js 
toObject ms: 469
Done

[vkarpov15]

I'm going to merge this PR and ship with 8.3.4. But going to keep working on this because the performance improvements are quite substantial, and we could really stand to simplify the options parsing logic in $toObject().