Onchange escape

[joedolson]

This modifies the scripting for the category and archives widget dropdown select to prevent esc from submitting the form.

Because the key event is not part of the e object for a change event, this requires adding three separate event listeners: a listener in keydown to notice the esc key and record it in an attribute on the element; a listener on click to remove the attribute if the user later uses a mouse to activate the form; and modifications to the existing onchange listener to handle navigation.

The onchange event now appears to require a short delay before execution to ensure that the DOM change is observed.

Trac ticket: https://core.trac.wordpress.org/ticket/63531

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[github-actions]

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[mukeshpanchal27]

Fix Lint errors

[github-actions]

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