mathlib3

d75314b3 - fix(data/nat/interval): do not dedup when implementing `finset.Icc` etc (#16423)

fix(data/nat/interval): do not dedup when implementing `finset.Icc` etc (#16423) This means that `finset.Iic n` no longer has quadratic complexity. `#eval (finset.Iic 200000).card` is now almost instant rather than taking a very long time.