Add `waitUntilNextScheduling`

[dubzzz]

💡 Idea

While not critical, in some cases it might be simpler to have a built-in way to wait for the next task to be scheduled (without releasing anything or with releasing?).

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.