[DOCS] Fixes title out of sequence warnings in breaking changes (elas…

…tic#63213) (elastic#63749)

* [DOCS] Add discrete attributes

* [DOCS] Addresses title out of sequence warnings

* [DOCS] Fixes some formatting in doc

* [DOCS] More formatting changes

* [DOCS] More clean-up of breaking changes docs

* [DOCS] Adds more developer breaking changes

* [DOCS] Incorporates review comments

* [DOCS] Fixes formatting

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

Co-authored-by: Lisa Cawley <[email protected]>