Minor improvements in the "mix release" docs
Minor improvements in the "mix release" docs

[ci skip]

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