After watching some hermits struggle to fight a run-away wither mid-air for the second season in a row, I decided runaway altitude withers might be a niche problem in want of a nichesolution.
	Thanks to @joeHills for this particular boquette of whoopsiedaisies.

This lightweight pack only runs once every five minutes when inactive and switches to active only when it detects a wither above a specified y-value (y=144).

While active, this pack both encourages problematic withers to descend and prevents them from ascending by teleporting them exactly downward at exactly their maximum upward volocity each tick.
	This version of the pack also detects the ground below while moving the wither down, and only lowers the wither until it hovers a set distance above the ground (configurable in tick.mcfunction).
	I've configure this hovering distance to 5 blocks above the ground by default, as that's most similar to vanilla behavior which still allows the pack to function as intended.
		
When a wither descends below a specified y-value (y=132) or dies, if doing so means that there are no more problematic withers, this pack returns to its' inactive state.

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While not an intended use of the pack, it's worth noting that specific combinations of the predicates' y-values and the hovering distance would make withers-mining a safer and more stable activity,
	By holding the wither within the optimal range of y values for wither mining.
