perf: use while! in tryTail inner loop, removing redundant mutable go flag

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

release-notes.txt

@@ -8,6 +8,7 @@ Release notes:
     - perf: TaskSeq.chunkBy and chunkByAsync reuse the ResizeArray buffer between chunks, reducing allocations on sequences with many chunk boundaries
     - fixes: TaskSeq.insertAt, insertManyAt, removeAt, removeManyAt, updateAt now raise ArgumentNullException (not NullReferenceException) when given a null source; insertManyAt also validates the values argument
     - refactor: simplify lengthBy and lengthBeforeMax to use while! and remove the redundant mutable 'go' and initial MoveNextAsync
+    - refactor: simplify tryTail inner loop to use while!, removing redundant mutable 'go' flag and initial MoveNextAsync
     - adds TaskSeq.distinctUntilChangedWith and TaskSeq.distinctUntilChangedWithAsync, #345
     - adds TaskSeq.withCancellation, #167
     - adds TaskSeq.replicateInfinite, replicateInfiniteAsync, replicateUntilNoneAsync, #345

src/FSharp.Control.TaskSeq/TaskSeqInternal.fs

@@ -845,14 +845,8 @@ module internal TaskSeqInternal =
             | true ->
                 return
                     taskSeq {
-                        let mutable go = true
-                        let! step = e.MoveNextAsync()
-                        go <- step
-
-                        while go do
+                        while! e.MoveNextAsync() do
                             yield e.Current
-                            let! step = e.MoveNextAsync()
-                            go <- step
                     }
                     |> Some
         }