dorothy: fix ci: use /dev/stderr not /dev/tty

/ref 93490f4

commands/dorothy

@@ -1161,13 +1161,12 @@ function dorothy() (
  esac
  done
 
- # prepare, without conflating stdout
+ # prepare
  {
  ensure_dorothy_configured
  assert_dorothy_configured
  ensure_minimal_dependencies
- echo sup
- } &>/dev/tty
+ } >/dev/stderr # don't conflate stdout, don't use /dev/tty as tty doesn't exist on CI
 
  # run the command, inheriting our preconfigured environment
  ("${args[@]}")
@@ -1399,12 +1398,12 @@ function dorothy() (
  # Act
 
  # ensure the prerequisites are installed in case the user skipped them
- ensure_prereq_dependencies &>/dev/tty # don't conflate stdout/stderr for benefit of [dorothy run]
+ ensure_prereq_dependencies >/dev/stderr # don't conflate stdout, don't use /dev/tty as tty doesn't exist on CI
 
  # all helpers are defined, and argument overrides are handled
  # so prepare the local environment context with what is necessary for dorothy
  # such that the following [choose-option] will be found
- prepare_dorothy &>/dev/tty # don't conflate stdout/stderr for benefit of [dorothy run]
+ prepare_dorothy >/dev/stderr # don't conflate stdout, don't use /dev/tty as tty doesn't exist on CI
 
  if test "$(type -t "act_$action")" = 'function'; then
  "act_$action" "${args[@]}"