1.19.0

1.19.0

• new lint: user_super_initializers
• new lint: use_enums
• new lint: used_colored_box
• performance improvements for sort_constructors
• doc improvements for always_use_package_imports,
  avoid_print, and avoid_relative_lib_imports
• update avoid_void_async to skip main functions
• update prefer_final_parameters to not super on super params
• lint updates for enhanced-enums and super-initializer language
  features
• updated unnecessary_late to report on the variable name
• marked null_check_on_nullable_type_parameter stable