Autocomplete elements with combobox role are missing required children

## Description

Running a Lighthouse scan on a page with the autocomplete element will produce the following warning under the Accessibility section:

`Elements with an ARIA [role] that require children to contain a specific [role] are missing some or all of those required children.`

## Reproduction

**Steps**

1. Go to https://www.algolia.com/doc/ui-libraries/autocomplete/introduction/what-is-autocomplete/
2. Run a Lighthouse scan
3. Scroll down to the Accessibility section
4. See the warning

## Expected behavior

No accessibility warnings.

## Environment

- OS: Ubuntu 21.04
- Browser: Chrome 90.0.4430.212
- Autocomplete version: 1.0.1

Start by locating the autocomplete rendering entry point responsible for the combobox markup, then reproduce the Lighthouse warning using the linked documentation page and the reported environment. Check the rendered ARIA roles and required child roles. Done means the reproduction produces no accessibility warning.

Written by the indexing model from the issue text.