Fix vehicle test failures

[BrettDong]

Summary

Bugfixes "Fix vehicle test failures"

Purpose of change

Fix #51082.

Describe the solution

• Learn the recipe in vehicle rig crafting test, so the character can craft the desired item
• Clear vehicles before resetting player in vehicle power test, so the assertion that the player is not on a vehicle can succeed

Describe alternatives you've considered

Testing

Tests pass.

Additional context

Still doesn't explain why vehicle rig crafting test passes if running alone.