Option to calculate the max speed for the fastest travel time

🚧 THIS IS A TICKET MIGRATED FROM UPVOTY. The original ticket and comments will be available for a limited time over at:
https://abrp.upvoty.com/b/request-a-feature/option-to-calculate-the-max-speed-for-the-fastest-travel-time/
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Currently you need to keep adjusting the max speed to find the setting for the shortest travel time. An option to calculate the max. speed automatically would enhance the user experience by avoiding the need to adjust this setting many times before finding the best option.