mathlib3

9becea2d - feat(algebra/order/monoid_lemmas_zero_lt): add some lemmas about typeclasses (#14761)

feat(algebra/order/monoid_lemmas_zero_lt): add some lemmas about typeclasses (#14761) ~~Rename some instances for consistency.~~ Some git messages are from the previous PR. Maybe it's because I performed some improper operations. I didn't find out the way to remove them. Sorry for that.