fix: prevent calling viewport.resize() when isResizing

Author: jinwoo-choi-05

src/Flicking.ts

@@ -1715,6 +1715,8 @@ class Flicking extends Component<FlickingEvents> {
    * @return {this}
    */
   public async resize(): Promise<void> {
+    if (this._isResizing) return;
+    
     this._isResizing = true;
 
     const viewport = this._viewport;

src/core/AutoResizer.ts

@@ -75,12 +75,12 @@ class AutoResizer {
 
     const beforeSize = {
       width: flicking.viewport.width,
-      height: flicking.viewport.height,
+      height: flicking.viewport.height
     };
 
     const afterSize = {
       width: resizeEntryInfo.width,
-      height: resizeEntryInfo.height,
+      height: resizeEntryInfo.height
     };
 
     // resize 이벤트가 발생했으나 이전과 width, height의 변화가 없다면 이후 로직을 진행하지 않는다.