Uber and Lyft riders traveling out of Logan International Airport in Boston may face the highest rideshare charge in the world.Massport, the agency responsible for managing transit in Massachusetts, has proposed increasing the rideshare fees.The new plan would add $11.50 to a one-way trip and $23 to a roundtrip, making it the highest rideshare fee.The increased fees are due to the significant increase in rideshare traffic and the need to fund improvements to ground transportation.