outdated: use Formula#full_name

Closes Homebrew/homebrew#40265.

Signed-off-by: Xu Cheng <xucheng@me.com>

Library/Homebrew/cmd/outdated.rb

@@ -7,9 +7,9 @@ module Homebrew
 
     outdated = outdated_brews(formulae) do |f, versions|
       if ($stdout.tty? || ARGV.verbose?) && !ARGV.flag?("--quiet")
-        puts "#{f.name} (#{versions*', '} < #{f.pkg_version})"
+        puts "#{f.full_name} (#{versions*', '} < #{f.pkg_version})"
       else
-        puts f.name
+        puts f.full_name
       end
     end
     Homebrew.failed = ARGV.resolved_formulae.any? && outdated.any?