Combine use of Async.singleton & Async.retn #267
Description
Is your feature request related to a problem? Please describe.
Currently, we have two functions within the Async module which do the same thing https://github.com/demystifyfp/FsToolkit.ErrorHandling/blob/master/src/FsToolkit.ErrorHandling/Async.fs#L6-L12
Describe the solution you'd like
Removing either Async.retn or Async.singleton and replacing all references with the other would be the easiest solution. We might consider having a period where we convert and use the [<Obsolete>] attribute to announce the transition?
Additional context
Since this would be a breaking change, would this be worthwhile to add to the v5 changes coming soon?