Remove unreachable branch

Requirements meeting this condition are skipped by the first branch
on the caller side:

https://github.com/Homebrew/homebrew/blob/6c54de812f00658404501719d315202a5551cc1b/Library/Homebrew/formula_installer.rb

Library/Homebrew/formula_installer.rb

@@ -237,7 +237,6 @@ class FormulaInstaller
 
   def install_requirement_default_formula?(req, dependent, build)
     return false unless req.default_formula?
-    return false if build.without?(req) && (req.recommended? || req.optional?)
     return true unless req.satisfied?
     install_bottle_for?(dependent, build) || build_bottle?
   end