Investigate Meteor oplog test failures

[b1ron]

Refs FerretDB/FerretDB/pull/3925

One just times out and one returns $natural sort for non-capped collection is not supported.

Needs more investigation.

### Tasks
- [x] meteor-oplog-cursor-supported FerretDB/FerretDB/issues/3943
- [ ] meteor-oplog-entry-skipping
- [ ] meteor-oplog-x-implicit-collection-creation

[rumyantseva]

@b1ron did you create oplog collection manually? Something like db.createCollection("oplog.rs", {capped: true, size: 1024000}). FerretDB doesn't create oplog collection automatically, so you can see this error in case oplog was created as a regular collection, not a capped collection.

[b1ron]

@rumyantseva yes I did create the oplog before running the tests, still seeing failures. I will do some more investigation.