Fix ProfileCallback#handle_command when an item is linked to a different channel type

[jimtng]

This failed because handle_command tried to call ColorItem#format_command when the channel is a String and should be able to handle any string, not related to a color

profile("test") do |event, command:, callback:|
  logger.warn "Profile called #{event} #{command}"
  case event
  when :command_from_item
    logger.warn("command_from_item: #{command} #{command.class}")
    callback.handle_command("test")
  end
end

things.build do
  thing "astro:moon:test"
end

items.build do
  color_item "Color1" do
    channel "astro:moon:test:phase#name", profile: "ruby:test"
  end
end

Color1.command "0,100,100"