fix: Fix the issue of new process starting when exiting

[pengfeixx]

Fix the issue of new process starting when exiting

Bug: https://pms.uniontech.com/bug-view-290781.html
Log: Fix the issue of new process starting when exiting

[deepin-ci-robot]

deepin pr auto review

关键摘要:

• forceExit 函数中同时调用了 QApplication::exit(0) 和 _Exit(0)，这两个函数的作用是相同的，但 _Exit 是一个非标准的函数，可能会导致跨平台兼容性问题。
• MainWindow.qml 文件中的 VNoteMainManager.foreceExit(); 应该是 VNoteMainManager.forceExit();，拼写错误。

是否建议立即修改:

• 是

[deepin-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: lzwind, pengfeixx, rb-union

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