Clear exisiting listeners in SliderPreference.onBindViewHolder()

If the view is reused, the old listeners will still remain on the
instance and cause wrong behavior. Should clear the old listeners before
adding the new one.

Flag: EXEMPT update library
Test: visual test
Bug: 349675952
Bug: 385089184
Change-Id: Iaee4996132422bb0e0d41984cd7982df4bde67f6