Unexpected argument 'self-uninstall'

[Kyle-Ye]

The README states swiftly self-uninstall. But it is now not avaiable.

swiftly --help
OVERVIEW: A utility for installing and managing Swift toolchains.

USAGE: swiftly <subcommand>

OPTIONS:
  --version               Show the version.
  -h, --help              Show help information.

SUBCOMMANDS:
  install                 Install a new toolchain.
  list-available          List toolchains available for install.
  use                     Set the in-use or default toolchain. If no toolchain is provided, print the currently
                          in-use toolchain, if any.
  uninstall               Remove an installed toolchain.
  list                    List installed toolchains.
  update                  Update an installed toolchain to a newer version.
  init                    Perform swiftly initialization into your user account.
  self-update             Update the version of swiftly itself.
  run                     Run a command while proxying to the selected toolchain commands.
  link                    Link swiftly so it resumes management of the active toolchain.
  unlink                  Unlinks swiftly so it no longer manages the active toolchain.

  See 'swiftly help <subcommand>' for detailed help.

swiftly --version
1.1.1