Geocoder input hijacks focus when used in form

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### Overview

When using the geocoder outside of a map, as part of a form, pressing the `Enter` key in another field will bring the focus of the form to the geocoder input. This is unexpected behavior which prevents users from submitting forms via `Enter` and breaks the overall flow of filling out a form.

### Library Version

- [v4.7.0](https://github.com/mapbox/mapbox-gl-geocoder/tree/9d084c95d07f2f5db7f86a77c2b395472c1a0805)

### Reproducible Example

- Visit https://codepen.io/zoran/pen/RwRXxKj
- Click into any of the non-geocoder fields
- Press the `Enter` key

### Expected Behavior

- The `Enter` button should behave as it normally would in a form (i.e. submitting form when appropriate).

### Current Behavior

- The form changes focus to the geocoder input.

### Notes

- This issue doesn't seem to happen when the geocoder input is placed after the submit button, e.g.:

```html

```

Start with the linked CodePen reproduction and trace how the geocoder input handles Enter and focus when placed inside a form. Done means pressing Enter in another field follows normal form behavior, including submission when appropriate, without moving focus to the geocoder input.

Written by the indexing model from the issue text.