MeshCollisionTraversalNodeRSS: cleanup template declarations

[SpaceIm]

Some warnings reported by Visual Studio:

In fcl::MeshCollisionTraversalNodeRSS, these 2 templates are never defined afterwards:

bool BVTesting(int b1, int b2, const Transform3<S>& tf) const;

void leafTesting(int b1, int b2, const Transform3<S>& tf) const;

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