feat: add swift implementation to lcci problem: No.05.06 (doocs#2669)

Author: klever34

lcci/05.06.Convert Integer/README.md

@@ -91,6 +91,14 @@ impl Solution {
 }
 ```
 
+```swift
+class Solution {
+    func convertInteger(_ A: Int, _ B: Int) -> Int {
+        return (Int32(A) ^ Int32(B)).nonzeroBitCount
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/05.06.Convert Integer/README_EN.md

@@ -108,6 +108,14 @@ impl Solution {
 }
 ```
 
+```swift
+class Solution {
+    func convertInteger(_ A: Int, _ B: Int) -> Int {
+        return (Int32(A) ^ Int32(B)).nonzeroBitCount
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- end -->

lcci/05.06.Convert Integer/Solution.swift

@@ -0,0 +1,5 @@
+class Solution {
+    func convertInteger(_ A: Int, _ B: Int) -> Int {
+        return (Int32(A) ^ Int32(B)).nonzeroBitCount
+    }
+}