message: fix concept checks on span template type deduction
diff: @@ -320,13 +320,13 @@ namespace ranges
  #if RANGES_CXX_DEDUCTION_GUIDES >= RANGES_CXX_DEDUCTION_GUIDES_17
  CONCEPT_template(typename Rng)(
  requires ContiguousRange<Rng>() &&
  - range_cardinality<Rng>::value < cardinality{})
  + IsTrue<range_cardinality<Rng>::value < cardinality{}>())
  span(Rng &&rng) ->
  span<concepts::ContiguousRange::element_t<Rng>>;
  CONCEPT_template(typename Rng)(
  requires ContiguousRange<Rng>() &&
  - range_cardinality<Rng>::value >= cardinality{})
  + IsTrue<range_cardinality<Rng>::value >= cardinality{}>())
  span(Rng &&rng) ->
  span<concepts::ContiguousRange::element_t<Rng>,
  static_cast<detail::span_index_t>(range_cardinality<Rng>::value)>;
  