Controlled rollout of notifying about the `black`/`pylint`/`isort` extension.

[karthiknadig]

• [x] Add new experiment in the control tower @luabud
• [x] Add prompt to asking users to switch to using the new extensions.
  • [x] isort : We decided to replace the isort shipped with the extension to just use isort extension.
  • [x] black/autopep8 : We have to prompt users for each selected formatter.
  • [x] pylint/flake8 : We have to prompt users for each selected linter.

[karthiknadig]

@luabud How does this look like for the transition to extension?

flowchart TD
    start([start])
    finished([end])

    is_linter_enabled{Is Linter Enabled?}
    has_args{Has Linter args?}
    are_simple_args{Are simple args?}
    install_extensions{Install extensions?}

    show_prompt[Show prompt]
    no_prompt[No prompt]

    trigger_install[trigger install]
    copy_args[Copy arguments]

    start --> is_linter_enabled

    is_linter_enabled -- yes --> has_args
    is_linter_enabled -- no --> no_prompt

    has_args -- yes --> are_simple_args
    has_args -- no --> show_prompt 

    are_simple_args -- yes --> show_prompt
    are_simple_args -- no --> no_prompt

    show_prompt --> install_extensions 

    install_extensions -- no --> finished
    install_extensions -- yes --> trigger_install

    trigger_install --> copy_args

    copy_args --> finished
    no_prompt --> finished

[luabud]

This looks good to me! If users don't have args, wouldn't we want to transition them to the new extensions as well?

[karthiknadig]

@luabud Can you verify this when you get the chance for Formatting prompt?