[3.13] Doc: Simplify the definition of 'soft deprecated' (GH-124988) (#125029)

Doc: Simplify the definition of 'soft deprecated' (GH-124988)
(cherry picked from commit feca4cf64e9742b9c002d5533ced47e68b34a880)

Co-authored-by: Andrés Delfino <adelfino@gmail.com>
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>
Co-authored-by: Carol Willing <carolcode@willingconsulting.com>