Bring back `test_bin_to_color` unit test

[benjamin051000]

vga-simulator/test_vga_sim.py

Lines 11 to 18 in cb34f55

	def test_bin_to_color(self):
	# for i in range(1, 5):
	# self.assertEqual(vga_sim.bin_to_color(0, i), 0)
	#
	# self.assertEqual(vga_sim.bin_to_color(1, 1), 255)
	# self.assertEqual(vga_sim.bin_to_color(3, 2), 255)
	# self.assertEqual(vga_sim.bin_to_color(7, 3), 255)
	pass

I'm not sure why it was removed. Is it able to be brought back?