mathlib3

905d887f - chore(field_theory/ratfunc): to_fraction_ring_ring_equiv (#10806)

chore(field_theory/ratfunc): to_fraction_ring_ring_equiv (#10806) Rename the underlying `ratfunc.aux_equiv` for discoverability. Co-authored-by: Yakov Pechersky <ffxen158@gmail.com>