Remove weighted subrun of weight weight from l at index i.
Examples:
abjad> l = [1, 1, 2, 3, 5, 5, 1, 2, 5, 5, 6]
abjad> listtools.remove_weighted_subrun_at(l, 8, 0)
[4, 5, 1, 2, 5, 5, 6]
abjad> l = [1, 1, 2, 3, 5, 5, 1, 2, 5, 5, 6]
abjad> listtools.remove_weighted_subrun_at(l, 13, 4)
[1, 1, 2, 3, 5, 5, 6]