br,lightning: add docs describing new S3 URL params (#11438)
br,lightning: add docs describing new S3 URL params (#11438)

* br,lightning: add docs describing new S3 URL options

* Apply suggestions from code review

Co-authored-by: Ran <7f7bd8069d9b07393cb2970c496702ddb954cbe5@gmail.com>

* fix md syntax problem

* Add periods

Co-authored-by: Ran <7f7bd8069d9b07393cb2970c496702ddb954cbe5@gmail.com>
Co-authored-by: shichun-0415 <21e49396de21ba1999fa7edf9177e7d3573ecd23@users.noreply.github.com>
pingcap/docs-cn,pingcap/docs-cn