Improve docker pull behaviour

[skjnldsv]

Hey! Thank you so much for this library. I really enjoyed working with it and will keep doing so! 🙏

I had some issues about docker pull and async/await race conditions
Following #357, I had to implement that

console.log('Pulling images... ⏳')
await new Promise((resolve, reject): any => docker.pull(SERVER_IMAGE, (err, stream) => {
	// https://github.com/apocas/dockerode/issues/357
	docker.modem.followProgress(stream, onFinished)
	function onFinished(err, output) {
		if (!err) {
			resolve(true)
			return
		}
		reject(err)
	}
}))
console.log(`└─ Done`)

Unfortunately, I think we could largely improve from the current behaviour.
The code I would like to see would be the following:

console.log('Pulling images... ⏳')
await docker.pull(SERVER_IMAGE)
console.log(`└─ Done`)

Could you explain the reasoning behind this implementation @apocas ? :)

---

Error details

```js Error: (HTTP code 404) no such container - No such image: ghcr.io/nextcloud/continuous-integration-shallow-server:latest at /home/runner/work/viewer/viewer/node_modules/docker-modem/lib/modem.js:336:17 at getCause (/home/runner/work/viewer/viewer/node_modules/docker-modem/lib/modem.js:366:7) at Modem.buildPayload (/home/runner/work/viewer/viewer/node_modules/docker-modem/lib/modem.js:335:5) at IncomingMessage. (/home/runner/work/viewer/viewer/node_modules/docker-modem/lib/modem.js:303:16) at IncomingMessage.emit (node:events:402:35) at IncomingMessage.emit (node:domain:475:12) at endReadableNT (node:internal/streams/readable:1343:12) at processTicksAndRejections (node:internal/process/task_queues:83:21) { reason: 'no such container', statusCode: 404, json: { message: 'No such image: ghcr.io/nextcloud/continuous-integration-shallow-server:latest' } ```

[deefactorial]

any update on this issue @apocas

[scubbo]

+1, would love to see an update on this. Ideally, callbacks wouldn't be required at all.

[Tzvetelin88]

+1.
I see

await docker.pull(image)

is supported, but it actually doesn't work properly. Function completes, but the image is still not there, and after some time it appears.

[nextend]

I had an issue when await docker.pull(image) kept a stream open and mocha could not end the process. This code solved the issue: #703 (comment)