Geocoder input reinitializes repeatedly in dev mode (react + useEffect)

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System Info
---
OS macOS 10.13.6 High Sierra
Node version 14.15
Libraries:
- mapbox-gl
- MapboxGeocoder
- create-react-app
- tailwindcss@2
- craco

Symptoms
---

I'm using the geocoder js library in a react application and seeing that the input is rendered each time my development server restarts (create react app fast refresh). I believe the appropriate enhancement is to provide a clean up function to remove the geocoder on component unmount, similar to the `map.remove()` function provided by `mapboxgl.Map()` as per the [react example repo](https://github.com/mapbox/mapbox-react-examples/blob/master/basic/src/Map.js#L8)

Code sample
---
```
import { useEffect } from 'react'
import mapboxgl from 'mapbox-gl'
import MapboxGeocoder from '@mapbox/mapbox-gl-geocoder'
import '@mapbox/mapbox-gl-geocoder/dist/mapbox-gl-geocoder.css'

const geocoder = new MapboxGeocoder({
accessToken: process.env.REACT_APP_MB_TOKEN,
mapboxgl: mapboxgl
})

export default function Autocomplete() {
useEffect(() => {
geocoder.addTo('#location')
geocoder.on('result', function ({ result }) {
console.dir(result)
})
}, [])
return

Start at the geocoder.addTo call in the provided React useEffect and compare its lifecycle with the linked React example's map.remove pattern. Inspect the geocoder control's existing cleanup behavior and determine how unmounting should affect the rendered input and registered result handler. Done means development-server refreshes no longer leave duplicate geocoder inputs.

Written by the indexing model from the issue text.