Positions TupletNumber correctly when Script and Slur are present.
There was previously a circular dependency that went:
TupletNumber needs TupletBracket position
TupletBracket needs Script position
Script with avoid-slur set to around or outside needs Slur position
Slur needs TupletNumber position
This is avoided by not doing Script vs TupletBracket collision
avoidance for Scripts that (a) are encompassed by a slur; and (b)
have avoid-slur set to outside or around. The worst-case scenario,
then, is the same collision that would have been present before
Slur vs TupletBracket collision avoidance was implemented. A more
thorough solution would be to have an avoid-tuplet-bracket property
that functions like avoid-slur.