optimize drag behavior performance #5918

Describe the bug / 问题描述

DragElement can avoid to re-calculate mapper style

Reproduction link / 重现链接

No response

Steps to Reproduce the Bug or Issue / 重现步骤

No response

G6 Version / G6 版本

🆕 5.x

Operating System / 操作系统

macOS

Browser / 浏览器

Chrome

Additional context / 补充说明

No response