fix(window): use button property for data-tauri-drag-region left mouse button detection (#590)

plugins/window/src/scripts/drag.js

@@ -3,7 +3,7 @@
 // SPDX-License-Identifier: MIT
 
 document.addEventListener("mousedown", (e) => {
-  if (e.target.hasAttribute("data-tauri-drag-region") && e.buttons === 1) {
+  if (e.target.hasAttribute("data-tauri-drag-region") && e.button === 0) {
     // prevents text cursor
     e.preventDefault();
     // fix #2549: double click on drag region edge causes content to maximize without window sizing change