Update sets on slider input change using arrows

[jdmartinez]

Warmup sets don't update when weight is changed using input arrow buttons. In a desktop browser you have to click elsewhere to update sets.

[nmunson]

@jdmartinez thanks for this PR. When testing it I see that it does correctly fix the problem you described, but it hurts the performance of using the slider when dragging and dropping. I think it's trying to calculate each intermediate step before dropping the slider. Let me know if you have ideas about fixing that or I can close this PR out.