make sync-default-gems GEM=irb

from ruby/irb@96f05e7.

Just syncing newer test changes so that conflicts do not happen when trunk is
modified and we need to backport that to ruby/irb.

test/irb/test_color.rb

@@ -31,13 +31,8 @@ def test_colorize_code
         "yield(hello)" => "#{GREEN}yield#{CLEAR}(hello)",
         '"##@var]"' => "#{RED}\"#{CLEAR}#{RED}##{CLEAR}#{RED}##{CLEAR}@var#{RED}]#{CLEAR}#{RED}\"#{CLEAR}",
         '"foo#{a} #{b}"' => "#{RED}\"#{CLEAR}#{RED}foo#{CLEAR}#{RED}\#{#{CLEAR}a#{RED}}#{CLEAR}#{RED} #{CLEAR}#{RED}\#{#{CLEAR}b#{RED}}#{CLEAR}#{RED}\"#{CLEAR}",
-      }.merge!(
-        if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.6.0')
-          { '/r#{e}g/' => "#{RED}\e[1m/#{CLEAR}#{RED}r#{CLEAR}#{RED}\#{#{CLEAR}e#{RED}}#{CLEAR}#{RED}g#{CLEAR}#{RED}\e[1m/#{CLEAR}" }
-        else
-          { '/r#{e}g/' => "#{RED}#{BOLD}/#{CLEAR}#{RED}r#{CLEAR}#{RED}\#{#{CLEAR}e#{RED}}#{CLEAR}#{RED}g#{CLEAR}#{RED}#{BOLD}/#{CLEAR}" }
-        end
-      ).each do |code, result|
+        '/r#{e}g/' => "#{RED}#{BOLD}/#{CLEAR}#{RED}r#{CLEAR}#{RED}\#{#{CLEAR}e#{RED}}#{CLEAR}#{RED}g#{CLEAR}#{RED}#{BOLD}/#{CLEAR}",
+      }.each do |code, result|
         assert_equal(result, with_term { IRB::Color.colorize_code(code) }, "Case: colorize_code(#{code.dump})")
       end
     end