fix(onClickOutside): adjust shouldListen handling timing

[Doctor-wu]

Fix #3465

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Description

• Fix OnClickoutside: the callback was triggered accidentally when the target is undefined #3465 *
• Function: onClickOutside *

In current logic, if the target is falsy when the event trigger, it won't care about the ignore options which make no sense.
This PR change the logic to judge if should ignore at first before any other judgements related with el.

Additional context

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🤖 Generated by Copilot at d5915d8

Refactored shouldListen variable in onClickOutside hook to use a single logical expression and ensure boolean type. This improves the code readability and consistency.

🤖 Generated by Copilot at d5915d8

• Simplify the logic for shouldListen variable using a single expression (link)

[Doctor-wu]

thx for adjust~

[Doctor-wu]

I'll create a new PR to replace this