Given an array of seats, return the maximum number of new people which can be seated, as long as there is at least a gap of 2 seats between people.
0.1.maximumSeating([0, 0, 0, 1, 0, 0, 1, 0, 0, 0]) ➞ 2
// [1, 0, 0, 1, 0, 0, 1, 0, 0, 1]
maximumSeating([0, 0, 0, 0]) ➞ 2
// [1, 0, 0, 1]
maximumSeating([1, 0, 0, 0, 0, 1]) ➞ 0
// There is no way to have a gap of at least 2 chairs when adding someone else.