facet_grid with ordered factors and drop = FALSE causes deprecation warning

[ibuiltthis]

I found a problem with faceting in ggplot

I expected the plot to be produced with no warnings. The plot does work correctly as this is just a warning but will probably break in the future.

Here is the code to reproduce the bug:

library(tidyverse)

my_data <- tibble(
    things = factor(c("shoe", "sock", "bed", "curtain"), ordered = TRUE)
)
my_data_filtered <- my_data |> filter(things != "curtain")

ggplot(my_data_filtered) +
    geom_bar(
        aes(x = 1)
    ) +
    facet_grid(
        rows = vars(things),
        drop = FALSE
    )

# Warning message:
# Combining variables of class <ordered> and <factor> was deprecated in ggplot2 3.4.0.
# ℹ Please ensure your variables are compatible before plotting (location: `join_keys()`)
# This warning is displayed once every 8 hours.
# Call `lifecycle::last_lifecycle_warnings()` to see where this warning was generated. 

lifecycle::last_lifecycle_warnings()
# [[1]]
# <warning/lifecycle_warning_deprecated>
# Warning:
# Combining variables of class <ordered> and <factor> was deprecated in ggplot2 3.4.0.
# ℹ Please ensure your variables are compatible before plotting (location: `join_keys()`)
# ---
# Backtrace:
#      ▆
#   1. ├─base (local) `<fn>`(x)
#   2. ├─ggplot2:::print.ggplot(x)
#   3. │ ├─ggplot2::ggplot_build(x)
#   4. │ └─ggplot2:::ggplot_build.ggplot(x)
#   5. │   └─layout$setup(data, plot$data, plot$plot_env)
#   6. │     └─ggplot2 (local) setup(..., self = self)
#   7. │       └─base::lapply(...)
#   8. │         └─ggplot2 (local) FUN(X[[i]], ...)
#   9. │           └─ggplot2::map_data(...)
#  10. │             └─ggplot2:::join_keys(facet_vals, layout, by = vars)
#  11. │               └─ggplot2:::vec_rbind0(x[by], y[by])
#  12. │                 ├─ggplot2:::with_ordered_restart(...)
#  13. │                 │ └─base::withCallingHandlers(...)
#  14. │                 └─vctrs::vec_rbind(..., .error_call = .error_call)
#  15. │                   └─vctrs (local) `<fn>`()
#  16. │                     └─vctrs:::vec_ptype2.ordered.factor(...)
#  17. │                       └─vctrs::vec_default_ptype2(x, y, ...)
#  18. │                         ├─base::withRestarts(...)
#  19. │                         │ └─base (local) withOneRestart(expr, restarts[[1L]])
#  20. │                         │   └─base (local) doWithOneRestart(return(expr), restart)
#  21. │                         └─vctrs::stop_incompatible_type(...)
#  22. │                           └─vctrs:::stop_incompatible(...)
#  23. │                             └─vctrs:::stop_vctrs(...)
#  24. │                               └─rlang::abort(message, class = c(class, "vctrs_error"), ..., call = call)
#  25. │                                 └─rlang:::signal_abort(cnd, .file)
#  26. │                                   └─base::signalCondition(cnd)
#  27. └─ggplot2 (local) `<fn>`(`<vctrs__2>`)
#  28.   └─ggplot2:::deprecate_soft0("3.4.0", I(msg), details = desc)