Increased tuplet number font size causes collision

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\relative c' {
  \override TupletNumber.font-size = #10
  \times 2/3 { d d d }
}

Ideally, the tuplet number should avoid the collision by shifting up.  The 
bracket should shift up as well.
This is currently difficult, as the TupletNumber is a child of the tuplet 
bracket and therefore dependent on it for Y-offset.

Cheers,
MS