make shortened urls editable

src/app/services/urlshortener.service.ts

@@ -24,6 +24,10 @@ export class UrlShortenerService {
         return this.http.post(environment.apiUrl + "/url/shortener", shortendUrlModel);
     }
 
+    update(shortendUrlModel) {
+        return this.http.patch(environment.apiUrl + "/url/shortener", shortendUrlModel);
+    }
+
     delete(code) {
         return this.http.delete(environment.apiUrl + "/url/shortener/" + code);
     }