feat: Simplify light lock exception condition

lib/stoplight/color.rb

@@ -5,6 +5,5 @@ module Color
  GREEN = 'green'
  YELLOW = 'yellow'
  RED = 'red'
- LOCKABLE_COLORS = [GREEN, RED].freeze
  end
 end

lib/stoplight/light/runnable.rb

@@ -28,11 +28,10 @@ def run
  end
 
  def lock(color)
- raise Error::IncorrectColor unless Color::LOCKABLE_COLORS.include?(color)
-
  state = case color
  when Color::RED then State::LOCKED_RED
  when Color::GREEN then State::LOCKED_GREEN
+ else raise Error::IncorrectColor
  end
 
  safely { data_store.set_state(self, state) }

spec/stoplight/color_spec.rb

@@ -36,22 +36,4 @@
  expect(Stoplight::Color::RED).to be_frozen
  end
  end
-
- describe '::LOCKABLE_COLORS' do
- it 'is an array' do
- expect(Stoplight::Color::LOCKABLE_COLORS).to be_a(Array)
- end
-
- it 'is frozen' do
- expect(Stoplight::Color::LOCKABLE_COLORS).to be_frozen
- end
-
- it 'includes green color' do
- expect(Stoplight::Color::LOCKABLE_COLORS).to include(Stoplight::Color::GREEN)
- end
-
- it 'includes red color' do
- expect(Stoplight::Color::LOCKABLE_COLORS).to include(Stoplight::Color::RED)
- end
- end
 end