GHA: add a job scanning for "bad words" in markdown

This means words, phrases or things we have decided not to use - words that
are spelled right according to the dictionary but we want

GHA: add a job scanning for "bad words" in markdown

This means words, phrases or things we have decided not to use - words that
are spelled right according to the dictionary but we want to avoid. In the
name of consistency and better documentation.

Closes #12764

show more ...