org-notify dbus send message to KDE/Plasma caused desktop suspend and high CPU,memory resources.

Here is my config:
```elisp
(setq org-notify-audible nil)
(org-notify-add 'default
                '(:time "1h" :period "1h" :duration 8
                        :actions (-ding -notify/window)
                        :audible t))
(org-notify-start (* 60 2))
```

When I have about 10 deadline tasks to be reminded at once, dbus suspend desktop soon because send dbus message too fast?

Maybe add a sequence delay to improve this situation?

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