continuously slice an array (or string) at the provided continuous interval indexes.

const arr = Array(100).map((v, i) => i) // === [0, 1, 2, ..., 99]
const slices: ContinuousIntervals = [0, 20, 30, 70, undefined]
sliceContinuous(arr, slices) // === [[0, 1, 2, ..., 19], [20, 21, ..., 29], [30, ..., 69], [70, ..., 99]]