Ruby / Prism >= 4.1.0 allows trailing comma in method definition (#1178)

See "Allow trailing comma in method signature": ruby/prism#3920

This test is no longer passing because of the change in Prism.

Author: eikes

test/irb/test_color.rb

@@ -184,7 +184,6 @@ def test_colorize_code_complete_false
         "a, b#" => "a, b#{BLUE}#{BOLD}\##{CLEAR}",
         "a, b;" => "#{RED}#{REVERSE}a, b#{CLEAR};",
         "def f(a,#" => "#{GREEN}def#{CLEAR} #{BLUE}#{BOLD}f#{CLEAR}(a,#{BLUE}#{BOLD}\##{CLEAR}",
-        "def f(a,)" => "#{GREEN}def#{CLEAR} #{BLUE}#{BOLD}f#{CLEAR}(a#{RED}#{REVERSE},#{CLEAR})",
         "[*" => "[*",
         "f(*" => "f(*",
         "f(**" => "f(**",