Revert "fix: dde-file-manager crash"

[Johnson-zs]

Reverts #2003

[deepin-ci-robot]

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This pull-request has been approved by: Johnson-zs

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[deepin-ci-robot]

deepin pr auto review

关键摘要:

• 移除了与QApplication的aboutToQuit信号的连接，需要确认这是否是有意为之。
• 删除了watcher对象停止监视的代码，需要验证这是否会影响文件监视功能。
• 移除了workerThread的quit和wait方法，这可能会影响到线程的优雅退出。

是否建议立即修改:

• 是，需要确保移除aboutToQuit信号连接是有意为之，并且不会影响程序的预期行为。
• 是，需要验证删除watcher停止监视代码是否会影响文件监视功能。
• 是，需要确认移除workerThread的quit和wait方法是否会影响程序的线程管理。

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