Contains minor changes to async usage in line with upstream API changes.
I believe a feedback issue we were seeing with offset changes (the only
component using async write flow) may have been resolved by these
upstream changes (see [release
notes](https://github.com/realm/realm-dotnet/releases/tag/10.14.0)) but
am not investigating further just yet.
Closes https://github.com/ppy/osu/issues/18468.
This doesn't stop the tutorial from downloading a second time, but at
least displays the correct status afterwards. Avoiding the download is a
bit more involved and requires a change to the flow. Probably not worth
it just yet.
To test, recommend switching to production environment, as dev server
doesn't have correct metadata for tutorial resulting in weirdness.