Review Swift codes (#1150)

* feat(swift): review for chapter_computational_complexity

* feat(swift): review for chapter_data_structure

* feat(swift): review for chapter_array_and_linkedlist

* feat(swift): review for chapter_stack_and_queue

* feat(swift): review for chapter_hashing

* feat(swift): review for chapter_tree

* feat(swift): add codes for heap article

* feat(swift): review for chapter_heap

* feat(swift): review for chapter_graph

* feat(swift): review for chapter_searching

* feat(swift): review for chapter_sorting

* feat(swift): review for chapter_divide_and_conquer

* feat(swift): review for chapter_backtracking

* feat(swift): review for chapter_dynamic_programming

* feat(swift): review for chapter_greedy

* feat(swift): review for utils

* feat(swift): update ci tool

* feat(swift): trailing closure

* feat(swift): array init

* feat(swift): map index

codes/swift/chapter_tree/array_binary_tree.swift

@@ -48,7 +48,7 @@ class ArrayBinaryTree {
     func levelOrder() -> [Int] {
         var res: [Int] = []
         // 直接遍历数组
-        for i in stride(from: 0, to: size(), by: 1) {
+        for i in 0 ..< size() {
             if let val = val(i: i) {
                 res.append(val)
             }