Fix an "unused variable" warning in the String module (#7603)
Fix an "unused variable" warning in the String module (#7603)


lexmag/elixir,kelvinst/elixir,pedrosnk/elixir,ggcampinho/elixir,pedrosnk/elixir,ggcampinho/elixir,lexmag/elixir,kelvinst/elixir,kimshrier/elixir,kimshrier/elixir,michalmuskala/elixir,elixir-lang/elixir,joshprice/elixir