Enable disallowed-method and disallowed-type by default

[jplatte]

Could disallowed-method and disallowed-type be moved to restriction and made warn (or even deny) by default? I can't find any known issues with them and you need to configure them via .clippy.toml anyways before they do anything.

@rustbot label +C-enhancement

[taiki-e]

Filed #8261

@rustbot claim