119 enable user to hide the slide bar on forest plot

[fukuhiro2023]

This PR updates ae_forestly() so that a user can control the display of the slider bar. If NULL is specified in filter, the slider bar will not be displayed.

<Example 1. Default: filter = NULL>

adsl <- forestly::forestly_adsl_3grp
adae <- forestly::forestly_adae_3grp
meta_forestly(
  dataset_adsl = adsl,
  dataset_adae = adae,
) |>
  prepare_ae_forestly() |>
  format_ae_forestly(c("n", "prop", "fig_prop", "fig_diff", "diff")) |>
  ae_forestly()

<Example 2. filter = "n">

adsl <- forestly::forestly_adsl_3grp
adae <- forestly::forestly_adae_3grp
meta_forestly(
  dataset_adsl = adsl,
  dataset_adae = adae,
) |>
  prepare_ae_forestly() |>
  format_ae_forestly(c("n", "prop", "fig_prop", "fig_diff", "diff")) |>
  ae_forestly(filter = "n")

[wangben718]

Thank you so much @fukuhiro2023 !