feat: add ts solution to lc problem: No.2774 (doocs#1548)

Author: thinkasany

solution/2700-2799/2774.Array Upper Bound/README.md

@@ -81,4 +81,20 @@ Array.prototype.upperBound = function (target: number) {
 // [3,4,6,6,6,6,7].upperBound(6) // 5
 ```
 
+```ts
+declare global {
+    interface Array<T> {
+        upperBound(target: number): number;
+    }
+}
+
+Array.prototype.upperBound = function (target: number) {
+    return this.lastIndexOf(target);
+};
+
+// [3,4,5].upperBound(5); // 2
+// [1,4,5].upperBound(2); // -1
+// [3,4,6,6,6,6,7].upperBound(6) // 5
+```
+
 <!-- tabs:end -->

solution/2700-2799/2774.Array Upper Bound/README_EN.md

@@ -71,4 +71,20 @@ Array.prototype.upperBound = function (target: number) {
 // [3,4,6,6,6,6,7].upperBound(6) // 5
 ```
 
+```ts
+declare global {
+    interface Array<T> {
+        upperBound(target: number): number;
+    }
+}
+
+Array.prototype.upperBound = function (target: number) {
+    return this.lastIndexOf(target);
+};
+
+// [3,4,5].upperBound(5); // 2
+// [1,4,5].upperBound(2); // -1
+// [3,4,6,6,6,6,7].upperBound(6) // 5
+```
+
 <!-- tabs:end -->