Dropdown does not close on all blur events

We recently moved our application to this library from twitter-typeahead and have run into an issue where the results dropdown will only close when a selection is made. If a user clicks away from the input or tabs to the next form item the dropdown remains open.

This is inconvenient when a value for the field is already set and does not need to be changed. The user accidentally clicks the input or is tabbing through the page and the dropdown opens from the focus event, visually blocking the next form fields until the user makes the selection again.

Is this dropdown behavior intended? If so, could a prop be added so that implementers can turn it on or off?

If it isn't intended behavior, I think changing [this line](https://github.com/github/auto-complete-element/blob/main/src/autocomplete.ts#L250) to `this.interactingWithList = false` or possibly just removing that line altogether would fix things.

Start at src/autocomplete.ts line 250 and trace how blur, focus, and list interaction state control the dropdown. Confirm the intended behavior for clicking away and tabbing, then verify that the dropdown closes in both cases without breaking selection behavior.

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