A simple wrapper to handle IAsyncEnumerable in F#

IAsyncEnumerable.fs

type System.Collections.Generic.IAsyncEnumerable<'T> with
  member this.AsTask () = task {
    let mutable nxt = true
    let output = ResizeArray()
    let enumerator = this.GetAsyncEnumerator()
    while nxt do
      let! next = enumerator.MoveNextAsync()
      nxt <- next
      if nxt then output.Add enumerator.Current
    return output.ToArray()
  }