Weird behavior in DemoCrash

[tzaeschke]

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There are two issues, both point to a (two?) problems in the collider:

• Letting DemoCrash sit still for a few second will occasionally show the box stack becoming "active", as if one of the boxes moved slightly or was brushed by another object.
• Choosing ReorderingMethod.REORDERING_METHOD__DONT_REORDER in DxQuickStep line 147 causes DemoCrash to become unstable.

Both could be a good starting point for debugging a problem in DxQuickStep.