AVOID repeating const keyword in a const context

[furaiev]

First of all, thank you for great service!

Could you please adjust output ${name}_icons.dart file not to use repeating const?

linter rule: https://dart-lang.github.io/linter/lints/unnecessary_const.html

e.g

// current
static const IconData settings = const IconData(0xe801, fontFamily: _kFontFam);

// required
static const IconData settings = IconData(0xe801, fontFamily: _kFontFam);