Change to make keyword optional by default

lib/tty/option/parameter/keyword.rb

@@ -6,6 +6,9 @@ module TTY
   module Option
     class Parameter
       class Keyword < Parameter
+        def required?
+          @settings.fetch(:required) { false }
+        end
       end
     end # Parameter
   end # Option

spec/unit/parameter/keyword_spec.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+RSpec.describe TTY::Option::Parameter::Keyword do
+  context "required/optional setting" do
+    it "sets keyword presence optional by default" do
+      kwarg = described_class.new(:foo)
+
+      expect(kwarg.required?).to eq(false)
+      expect(kwarg.optional?).to eq(true)
+    end
+  end
+end