feat: add typescript solution to lc problem: No.0231.Power of Two (doocs#427)

Author: zhaocchen

solution/0200-0299/0231.Power of Two/README.md

@@ -84,6 +84,14 @@ func isPowerOfTwo(n int) bool {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function isPowerOfTwo(n: number): boolean {
+  return n > 0 && (n & (n - 1)) == 0;
+};
+```
+
 ### **...**
 
 ```

solution/0200-0299/0231.Power of Two/README_EN.md

@@ -109,6 +109,14 @@ func isPowerOfTwo(n int) bool {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function isPowerOfTwo(n: number): boolean {
+  return n > 0 && (n & (n - 1)) == 0;
+};
+```
+
 ### **...**
 
 ```

solution/0200-0299/0231.Power of Two/Solution.ts

@@ -0,0 +1,3 @@
+function isPowerOfTwo(n: number): boolean {
+    return n > 0 && (n & (n - 1)) == 0;
+  };