Heatsink - Some bugfixes and feedback adjustments

Hi again, made some quick changes and bugfixes after getting some feedback from 2 of the playtesters (ily)

Bugfixes:

• Audio issues related to the pause menu
• Audio issues related to restarting levels

Adjustments:

• Adjusted one of the arcs in the Canyon level by making it thinner and removing the outline of both arcs to reduce the feeling that they are actual obstacles on the map
• Increased the idle heatloss speed to make gliding more viable and reduce the need of breaking to lose heat
• Reduced the air-drag so you can go longer distances by enertia without losing much speed (this also makes the vehicle a bit faster)