chore(measure_theory/covering/besicovitch): Weaker import (#11763)
chore(measure_theory/covering/besicovitch): Weaker import (#11763)

We relax the `set_theory.cardinal_ordinal` import to the weaker `set_theory.ordinal_arithmetic` import. We also fix some trivial spacing issues in the docs.





leanprover-community/mathlib,leanprover-community/mathlib