Utah Circuit 2.5

This change is because the Ibishu 200BX Race Edition now runs out of gear at the end of the highway section. I don't know what has changed since August but I don't want to make a new transmission setup so I'll swap out the vehicle instead.
This change was also coming since you can try many more different (and aggresive) racing lines to lower your lap time in the Sunburst compared to the 200BX where you always wanted to straighten out your corner exit as much as possible, due to all the power breaking the rear wheels loose.
Which in all makes for more fun and of course that's what we're looking for with this scenario, right?

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Other small changes include...
-- A ~300 Kb file size reduction by using a 1920 x 1080 thumbnail image, compared to the old 2560 x 1080 images.
-- The .prefab files are slightly more organized, but I still plan on sorting them out further for those who choose to modify the scenarios.
-- Time to beat is now also 1:56 in the regular lap, as the old goal of below 2:00 was for the Ibishu 200BX Race Edition.

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Hope everyone's happy with the changes!