cli_progress_step: Simplified cli progress messages, with styling
In RonMobile/cli: Helpers for Developing Command Line Interfaces

This is a simplified progress bar, a single (dynamic) message, without progress units.

cli_progress_step(
  msg,
  msg_done = msg,
  msg_failed = msg,
  spinner = FALSE,
  class = if (!spinner) ".alert-info",
  current = TRUE,
  .auto_close = TRUE,
  .envir = parent.frame(),
  ...
)

`msg`	Message to show. It may contain glue substitution and cli styling. It can be updated via `cli_progress_update()`, as usual. It is style as a cli info alert (see `cli_alert_info()`).
`msg_done`	Message to show on successful termination. By default this it is the same as `msg` and it is styled as a cli success alert (see `cli_alert_success()`).
`msg_failed`	Message to show on unsuccessful termination. By default it is the same as `msg` and it is styled as a cli danger alert (see `cli_alert_danger()`).
`spinner`	Whether to show a spinner at the beginning of the line. To make the spinner spin, you'll need to call `cli_progress_update()` regularly.
`class`	cli class to add to the message. By default there is no class for steps with a spinner.
`current`	Passed to `cli_progress_bar()`.
`.auto_close`	Passed to `cli_progress_bar()`.
`.envir`	Passed to `cli_progress_bar()`.
`...`	Passed to `cli_progress_bar()`.