renamer returning RichText causes issues

[mhinsch]

Returning Makie.RichText from a renamer produces an error complaining about a missing method isless for RichText. Adding the following fixes the problem and the plot looks as expected:

import Base.isless

Base.isless(rt1::Makie.RichText, rt2::Makie.RichText) = Base.isless(String(rt1), String(rt2))

[mhinsch]

Just to add, this can easily be reproduced with the tutorial example:

using AlgebraOfGraphics
using CairoMakie
using DataFrames

penguins = DataFrame(AlgebraOfGraphics.penguins())

layer_renamed = data(penguins) *
           mapping(
               :bill_length_mm,
               :bill_depth_mm,
               color = :species => renamer(["Adelie" => rich("Ad."), "Chinstrap" => rich("Ch."), "Gentoo" => rich("Ge.")]),
           ) *
           visual(Scatter)

draw(layer_renamed)

produces:

ERROR: MethodError: no method matching isless(::Makie.RichText, ::Makie.RichText)
The function `isless` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  isless(::Missing, ::Any)
   @ Base missing.jl:87
  isless(::Any, ::Missing)
   @ Base missing.jl:88
  isless(::Base.SHA1, ::Base.SHA1)
   @ Base loading.jl:140
  ...

Stacktrace:
  [1] isless(t1::Tuple{Makie.RichText}, t2::Tuple{Makie.RichText})
    @ Base ./tuple.jl:630
  [2] isless
    @ ./tuple.jl:630 [inlined]
  [3] isless
    @ ~/.julia/packages/AlgebraOfGraphics/uoww3/src/helpers.jl:16 [inlined]
  [4] lt
    @ ./ordering.jl:118 [inlined]
  [5] lt
    @ ./ordering.jl:126 [inlined]
  [6] _issorted
    @ ./sort.jl:1430 [inlined]
  [7] _sort!(v::Vector{…}, a::Base.Sort.StableCheckSorted{…}, o::Base.Order.Perm{…}, kw::@NamedTuple{…})
    @ Base.Sort ./sort.jl:1352
  [8] _sort!
    @ ./sort.jl:770 [inlined]
  [9] _sort!
    @ ./sort.jl:721 [inlined]
 [10] _sort!
    @ ./sort.jl:792 [inlined]
 [11] _sort!
    @ ./sort.jl:737 [inlined]
 [12] _sort!
    @ ./sort.jl:676 [inlined]
 [13] _sort!
    @ ./sort.jl:554 [inlined]
 [14] #sort!#32
    @ ./sort.jl:1694 [inlined]
 [15] sort!
    @ ./sort.jl:1687 [inlined]
 [16] _sortperm(A::Vector{…}; alg::Base.Sort.SubArrayOptimization{…}, order::Base.Order.ForwardOrdering, scratch::Nothing, dims::@Kwargs{})
    @ Base.Sort ./sort.jl:1895
 [17] _sortperm
    @ ./sort.jl:1882 [inlined]
 [18] #sortperm#36
    @ ./sort.jl:1879 [inlined]
 [19] sortperm
    @ ./sort.jl:1868 [inlined]
 [20] sortperm
    @ ~/.julia/packages/StructArrays/n5wxA/src/sort.jl:57 [inlined]
 [21] GroupPerm
    @ ~/.julia/packages/StructArrays/n5wxA/src/sort.jl:11 [inlined]
 [22] permutation_ranges(cols::Tuple{Vector{AlgebraOfGraphics.Sorted{Makie.RichText}}})
    @ AlgebraOfGraphics ~/.julia/packages/AlgebraOfGraphics/uoww3/src/algebra/processing.jl:8
 [23] group(processedlayer::ProcessedLayer)
    @ AlgebraOfGraphics ~/.julia/packages/AlgebraOfGraphics/uoww3/src/algebra/processing.jl:55
 [24] process(layer::Layer)
    @ AlgebraOfGraphics ~/.julia/packages/AlgebraOfGraphics/uoww3/src/algebra/processing.jl:163
 [25] ProcessedLayers
    @ ~/.julia/packages/AlgebraOfGraphics/uoww3/src/algebra/layers.jl:68 [inlined]
 [26] compute_axes_grid(d::Layer, scales::AlgebraOfGraphics.Scales; axis::Dictionaries.Dictionary{Symbol, Any})
    @ AlgebraOfGraphics ~/.julia/packages/AlgebraOfGraphics/uoww3/src/algebra/layers.jl:301
 [27] compute_axes_grid
    @ ~/.julia/packages/AlgebraOfGraphics/uoww3/src/algebra/layers.jl:299 [inlined]
 [28] #_draw#395
    @ ~/.julia/packages/AlgebraOfGraphics/uoww3/src/draw.jl:169 [inlined]
 [29] _draw
    @ ~/.julia/packages/AlgebraOfGraphics/uoww3/src/draw.jl:166 [inlined]
 [30] draw(d::Layer, scales::AlgebraOfGraphics.Scales; axis::@NamedTuple{}, figure::@NamedTuple{}, facet::@NamedTuple{}, legend::@NamedTuple{}, colorbar::@NamedTuple{}, palette::Nothing)
    @ AlgebraOfGraphics ~/.julia/packages/AlgebraOfGraphics/uoww3/src/draw.jl:97
 [31] draw
    @ ~/.julia/packages/AlgebraOfGraphics/uoww3/src/draw.jl:87 [inlined]
 [32] draw(d::Layer)
    @ AlgebraOfGraphics ~/.julia/packages/AlgebraOfGraphics/uoww3/src/draw.jl:87
 [33] top-level scope
    @ REPL[8]:1
Some type information was truncated. Use `show(err)` to see complete types.