transitivity vs. trans?

Stream: mathlib4

[Thomas Murrills]

We have both a trans tactic (which uses the @[trans] attribute) and a transitivity tactic (which is just a macro that applies Nat.l(e/t)_trans). From the blame I'm guessing the latter was a temporary fix from before the trans tactic existed. Can we now just make transitivity mean trans?

[Ruben Van de Velde]

Sounds good