On Chrome and Firefox for Windows, the dropdown format for Category and Archives widgets will submit if the user closes the `select` element using Escape. Escape should instead cancel the action.
Fix the classic Category and Archives widgets to prevent submission on `esc` keypresses.
Props adrock42, sabernhardt, whyisjake, westonruter, joedolson, nikunj8866, fakhriaz, mukesh27.
Fixes#63531.
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