mathlib3

47182da5 - feat(algebra/group/to_additive): add to_additive doc string linter (#12487)

feat(algebra/group/to_additive): add to_additive doc string linter (#12487) it is an easy mistake to add a docstring to a lemma with `to_additive` without also passing a string to `to_additive`. This linter checks for that, and suggests to add a doc string when needed.