docs: add AsyncSeq.min/max/minBy/maxBy to 4.1.0 release notes

PR #243 was merged after this release branch was created; include the
six new min/max aggregation combinators in the 4.1.0 changelog entry.

Co-authored-by: Copilot <[email protected]>

Author: github-actions[bot]

RELEASE_NOTES.md

@@ -3,6 +3,7 @@
 * Added `AsyncSeq.windowed` — produces a sliding window of a given size over an async sequence ([PR #241](https://github.com/fsprojects/FSharp.Control.AsyncSeq/pull/241)).
 * Added `AsyncSeq.reduce` and `AsyncSeq.reduceAsync` — folds without a seed value, mirroring `Seq.reduce` ([PR #242](https://github.com/fsprojects/FSharp.Control.AsyncSeq/pull/242)).
 * Added `AsyncSeq.sumBy`, `AsyncSeq.sumByAsync`, `AsyncSeq.average`, `AsyncSeq.averageBy`, and `AsyncSeq.averageByAsync` — numeric aggregation combinators mirroring the corresponding `Seq` module functions ([PR #245](https://github.com/fsprojects/FSharp.Control.AsyncSeq/pull/245)).
+* Added `AsyncSeq.min`, `AsyncSeq.max`, `AsyncSeq.minBy`, `AsyncSeq.maxBy`, `AsyncSeq.minByAsync`, and `AsyncSeq.maxByAsync` — min/max aggregation combinators mirroring `Seq.min`/`Seq.max`/`Seq.minBy`/`Seq.maxBy` ([PR #243](https://github.com/fsprojects/FSharp.Control.AsyncSeq/pull/243)).
 
 ### 4.0.0