Dashed line in line-column should have transparent bg

[landonreed]

Instead of using white for the various dashed lines in the narrative itinerary, we should use rgba(255, 255, 255, 0) (transparent) so that it can be used against non-white backgrounds.

otp-ui/packages/itinerary-body/src/otp-react-redux/line-column-content.js

Lines 17 to 51 in 0846151

	const cssBicycle = css`
	background: repeating-linear-gradient(
	0deg,
	red,
	red 8px,
	white 8px,
	white 12.5px
	);
	left: 7.5px;
	right: 7.5px;
	`;
	const cssCar = css`
	background: repeating-linear-gradient(
	0deg,
	grey,
	grey 8px,
	white 8px,
	white 12.5px
	);
	left: 7.5px;
	right: 7.5px;
	`;
	const cssMicromobility = css`
	background: repeating-linear-gradient(
	0deg,
	#f5a729,
	#f5a729 8px,
	white 8px,
	white 12.5px
	);
	left: 7.5px;
	right: 7.5px;
	`;