We have a fix for prefer_final_parameters and all prefer_final_foo lints, but we don't for avoid_final_parameters.

It should be really easy since we already have the Make variable '{0}' not final fix for assignment_to_final_local.

It could even become an assist, for people that don't have any related lints active but want to remove the previously added final from a declaration (and don't know we have the fix).

FYI @bwilkerson